Revert "Redefine task and its context"

36 files changed, 650 insertions, 510 deletions

diff --git a/node-admin/pom.xml b/node-admin/pom.xml
index 7b3b787b503..983e4d3a832 100644
--- a/node-admin/pom.xml
+++ b/node-admin/pom.xml
@@ -115,11 +115,6 @@
             <artifactId>mockito-core</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>com.google.jimfs</groupId>
-            <artifactId>jimfs</artifactId>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <build>
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/AdminComponent.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/AdminComponent.java
index 9888cca9c7e..9bed492bd76 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/AdminComponent.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/AdminComponent.java
@@ -1,8 +1,6 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.hosted.node.admin.component;
 
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
-
 /**
  * An AdminComponent cannot assume anything about the environment until enable()
  * is called: Required YUM packages may not have been installed, services
@@ -16,11 +14,6 @@ public interface AdminComponent {
     void enable();
 
     /**
-     * @return NodeAdminStateUpdater used by the REST API
-     */
-    NodeAdminStateUpdater getNodeAdminStateUpdater();
-
-    /**
      * Disable component. May be called more than once.
      * Must be compatible with component deconstruct().
      */
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/IdempotentTask.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/IdempotentTask.java
deleted file mode 100644
index b6b64dbf5dd..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/IdempotentTask.java
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.component;
-
-/**
- * This class is thread unsafe: All method calls MUST be exclusive and serialized.
- */
-public interface IdempotentTask {
-    String name();
-
-    /**
-     * Execute an administrative task to converge the system towards some ideal state.
-     *
-     * converge() must be idempotent: it may be called any number of times, or
-     * interrupted at any time e.g. by `kill -9`. The caller must ensure there is at
-     * most one invocation of converge() on this instance at any given time.
-     *
-     * @return false if the system was already converged, i.e. converge() was a no-op.
-     * @throws RuntimeException (or a subclass) if the task is unable to converge.
-     */
-    boolean converge(TaskContext context);
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskComponent.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskComponent.java
deleted file mode 100644
index c54f9ee00c8..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskComponent.java
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.component;
-
-import com.yahoo.component.ComponentId;
-import com.yahoo.component.chain.ChainedComponent;
-
-public abstract class TaskComponent extends ChainedComponent implements IdempotentTask {
-    protected TaskComponent(ComponentId id) {
-        super(id);
-    }
-
-    public String name() {
-        return getIdString();
-    }
-
-    public abstract boolean converge(TaskContext context);
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskContext.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskContext.java
deleted file mode 100644
index 9def627e87f..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/component/TaskContext.java
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.component;
-
-import java.nio.file.FileSystem;
-import java.util.EnumSet;
-import java.util.logging.Logger;
-
-public interface TaskContext {
-    enum Cloud { YAHOO, AWS }
-    Cloud cloud();
-
-    enum Role { TENANT_DOCKER_HOST, CONFIG_SERVER_DOCKER_HOST }
-    EnumSet<Role> roles();
-    default boolean hasRole(Role role) {
-        return roles().contains(role);
-    }
-
-    FileSystem fileSystem();
-
-    void logSystemModification(Logger logger, String actionDescription);
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/UnixPath.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/io/FileSystem.java
index 606f8cfb06e..c5c2df9e38e 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/UnixPath.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/io/FileSystem.java
@@ -1,5 +1,5 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
+package com.yahoo.vespa.hosted.node.admin.io;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
@@ -7,7 +7,7 @@ import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.OpenOption;
 import java.nio.file.Path;
-import java.nio.file.Paths;
+import java.nio.file.attribute.FileAttribute;
 import java.nio.file.attribute.GroupPrincipal;
 import java.nio.file.attribute.PosixFileAttributeView;
 import java.nio.file.attribute.PosixFileAttributes;
@@ -15,48 +15,52 @@ import java.nio.file.attribute.PosixFilePermission;
 import java.nio.file.attribute.PosixFilePermissions;
 import java.nio.file.attribute.UserPrincipal;
 import java.nio.file.attribute.UserPrincipalLookupService;
-import java.time.Instant;
 import java.util.Set;
 
-// @Immutable
-public class UnixPath {
-    private final Path path;
-
-    public UnixPath(Path path) {
-        this.path = path;
+/**
+ * File system operations to be mocked in unit tests.
+ */
+public class FileSystem {
+    public FileSystemPath withPath(Path path) {
+        return new FileSystemPath(this, path);
     }
 
-    public UnixPath(String path) {
-        this(Paths.get(path));
+    public boolean isDirectory(Path path) {
+        return path.toFile().isDirectory();
     }
 
-    public Path toPath() {
-        return path;
+    public boolean isRegularFile(Path path) {
+        return path.toFile().isFile();
     }
 
-    public void createParents() {
-        uncheck(() -> Files.createDirectories(path.getParent()));
+    public void createDirectory(Path path, FileAttribute<?>... attributes) {
+        uncheck(() -> Files.createDirectory(path, attributes));
     }
 
-    public String readUtf8File() {
+    public String readUtf8File(Path path) {
         byte[] byteContent = uncheck(() -> Files.readAllBytes(path));
         return new String(byteContent, StandardCharsets.UTF_8);
     }
 
-    public void writeUtf8File(String content, OpenOption... options) {
+    public void writeUtf8File(Path path, String content, OpenOption... options) {
         byte[] contentInUtf8 = content.getBytes(StandardCharsets.UTF_8);
         uncheck(() -> Files.write(path, contentInUtf8, options));
     }
 
-    public String getPermissions() {
-        return PosixFilePermissions.toString(getAttributes().permissions());
+    private PosixFileAttributes getAttributes(Path path) {
+        return uncheck(() ->
+                Files.getFileAttributeView(path, PosixFileAttributeView.class).readAttributes());
+    }
+
+    public String getPermissions(Path path) {
+        return PosixFilePermissions.toString(getAttributes(path).permissions());
     }
 
     /**
      * @param permissions Example: "rwxr-x---" means rwx for owner, rx for group,
      *                    and no permissions for others.
      */
-    public void setPermissions(String permissions) {
+    public void setPermissions(Path path, String permissions) {
         Set<PosixFilePermission> permissionSet;
         try {
             permissionSet = PosixFilePermissions.fromString(permissions);
@@ -68,35 +72,26 @@ public class UnixPath {
         uncheck(() -> Files.setPosixFilePermissions(path, permissionSet));
     }
 
-    public String getOwner() {
-        return getAttributes().owner().getName();
+    public String getOwner(Path path) {
+        return getAttributes(path).owner().getName();
     }
 
-    public void setOwner(String owner) {
+    public void setOwner(Path path, String owner) {
         UserPrincipalLookupService service = path.getFileSystem().getUserPrincipalLookupService();
         UserPrincipal principal = uncheck(() -> service.lookupPrincipalByName(owner));
         uncheck(() -> Files.setOwner(path, principal));
     }
 
-    public String getGroup() {
-        return getAttributes().group().getName();
+    public String getGroup(Path path) {
+        return getAttributes(path).group().getName();
     }
 
-    public void setGroup(String group) {
+    public void setGroup(Path path, String group) {
         UserPrincipalLookupService service = path.getFileSystem().getUserPrincipalLookupService();
         GroupPrincipal principal = uncheck(() -> service.lookupPrincipalByGroupName(group));
         uncheck(() -> Files.getFileAttributeView(path, PosixFileAttributeView.class).setGroup(principal));
     }
 
-    public Instant getLastModifiedTime() {
-        return uncheck(() -> Files.getLastModifiedTime(path)).toInstant();
-    }
-
-    private PosixFileAttributes getAttributes() {
-        return uncheck(() ->
-                Files.getFileAttributeView(path, PosixFileAttributeView.class).readAttributes());
-    }
-
     @FunctionalInterface
     private interface SupplierThrowingIOException<T> {
         T get() throws IOException;
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemPath.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemPath.java
new file mode 100644
index 00000000000..bfec341e05c
--- /dev/null
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemPath.java
@@ -0,0 +1,68 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.io;
+
+import java.nio.file.OpenOption;
+import java.nio.file.Path;
+import java.nio.file.attribute.FileAttribute;
+
+/**
+ * Convenience class for calling FileSystem methods on a fixed Path.
+ */
+public class FileSystemPath {
+    private final FileSystem fileSystem;
+    private final Path path;
+
+    FileSystemPath(FileSystem fileSystem, Path path) {
+        this.fileSystem = fileSystem;
+        this.path = path;
+    }
+
+    public boolean isDirectory() {
+        return fileSystem.isDirectory(path);
+    }
+
+    public boolean isRegularFile() {
+        return fileSystem.isRegularFile(path);
+    }
+
+    public FileSystemPath createDirectory(FileAttribute<?>... attributes) {
+        fileSystem.createDirectory(path, attributes);
+        return this;
+    }
+
+    public String readUtf8File() {
+        return fileSystem.readUtf8File(path);
+    }
+
+    public FileSystemPath writeUtf8File(String content, OpenOption... options) {
+        fileSystem.writeUtf8File(path, content, options);
+        return this;
+    }
+
+    public String getPermissions() {
+        return fileSystem.getPermissions(path);
+    }
+
+    public FileSystemPath setPermissions(String permissions) {
+        fileSystem.setPermissions(path, permissions);
+        return this;
+    }
+
+    public String getOwner() {
+        return fileSystem.getOwner(path);
+    }
+
+    public FileSystemPath setOwner(String owner) {
+        fileSystem.setOwner(path, owner);
+        return this;
+    }
+
+    public String getGroup() {
+        return fileSystem.getGroup(path);
+    }
+
+    public FileSystemPath setGroup(String group) {
+        fileSystem.setGroup(path, group);
+        return this;
+    }
+}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/DockerAdminComponent.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/DockerAdminComponent.java
index db0313583db..8ba93e769e5 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/DockerAdminComponent.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/DockerAdminComponent.java
@@ -18,7 +18,6 @@ import com.yahoo.vespa.hosted.node.admin.noderepository.NodeRepository;
 import com.yahoo.vespa.hosted.node.admin.noderepository.NodeRepositoryImpl;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.Orchestrator;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.OrchestratorImpl;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.node.admin.util.ConfigServerHttpRequestExecutor;
 import com.yahoo.vespa.hosted.node.admin.util.Environment;
 
@@ -42,7 +41,7 @@ public class DockerAdminComponent implements AdminComponent {
 
     private ConfigServerHttpRequestExecutor requestExecutor;
 
-    private Optional<NodeAdminStateUpdaterImpl> nodeAdminStateUpdater = Optional.empty();
+    private Optional<NodeAdminStateUpdater> nodeAdminStateUpdater = Optional.empty();
 
     public DockerAdminComponent(ConfigServerConfig configServerConfig,
                                 NodeAdminConfig config,
@@ -109,7 +108,7 @@ public class DockerAdminComponent implements AdminComponent {
                 metricReceiver,
                 clock);
 
-        nodeAdminStateUpdater = Optional.of(new NodeAdminStateUpdaterImpl(
+        nodeAdminStateUpdater = Optional.of(new NodeAdminStateUpdater(
                 nodeRepository,
                 orchestrator,
                 storageMaintainer,
@@ -134,7 +133,6 @@ public class DockerAdminComponent implements AdminComponent {
         // TODO: Also stop docker
     }
 
-    @Override
     public NodeAdminStateUpdater getNodeAdminStateUpdater() {
         return nodeAdminStateUpdater.get();
     }
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminConfig.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminConfig.java
index df26bc2dee5..0be31ffdbae 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminConfig.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminConfig.java
@@ -7,16 +7,18 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 
 import java.io.File;
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
 
 @JsonIgnoreProperties(ignoreUnknown = true)
 public class NodeAdminConfig {
     private static final ObjectMapper mapper = new ObjectMapper();
 
     /**
-     * If null, the default admin component will be used.
+     * A list of components to enable instead of the default.
      */
-    @JsonProperty("main-component")
-    public String mainComponent = null;
+    @JsonProperty("components")
+    public List<String> components = new ArrayList<>();
 
     public enum Mode {
         aws_tenant,
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminMain.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminMain.java
index 3e9cb239890..4ee84d12b1d 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminMain.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminMain.java
@@ -10,9 +10,11 @@ import com.yahoo.vespa.hosted.dockerapi.Docker;
 import com.yahoo.vespa.hosted.dockerapi.metrics.MetricReceiverWrapper;
 import com.yahoo.vespa.hosted.node.admin.ConfigServerConfig;
 import com.yahoo.vespa.hosted.node.admin.component.AdminComponent;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
 
 import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
 import java.util.logging.Logger;
 import java.util.stream.Collectors;
 
@@ -22,8 +24,8 @@ import java.util.stream.Collectors;
  *  - It will "start" (only) the necessary components.
  *  - Other components MUST NOT try to start (typically in constructor) since the features
  *    they provide is NOT WANTED and possibly destructive, and/or the environment may be
- *    incompatible. For instance, trying to contact the Docker daemon too early will be
- *    fatal: the node admin may not have installed and started the docker daemon.
+ *    incompatible. For instance, trying to contact the Docker daemon too early will
+ *    be fatal: the node admin may not have installed and started the docker daemon.
  */
 public class NodeAdminMain implements AutoCloseable {
     private static final Logger logger = Logger.getLogger(NodeAdminMain.class.getName());
@@ -34,7 +36,9 @@ public class NodeAdminMain implements AutoCloseable {
     private final MetricReceiverWrapper metricReceiver;
     private final ClassLocking classLocking;
 
-    private AdminComponent mainAdminComponent = null;
+    private List<AdminComponent> enabledComponents = new ArrayList<>();
+
+    private Optional<DockerAdminComponent> dockerAdmin = Optional.empty();
 
     public NodeAdminMain(ComponentRegistry<AdminComponent> adminRegistry,
                          ConfigServerConfig configServerConfig,
@@ -55,46 +59,53 @@ public class NodeAdminMain implements AutoCloseable {
 
     public void start() {
         NodeAdminConfig config = getConfig();
-        mainAdminComponent = selectAdminComponent(config);
-        mainAdminComponent.enable();
-    }
 
-    private AdminComponent selectAdminComponent(NodeAdminConfig config) {
-        if (config.mainComponent == null) {
-            return new DockerAdminComponent(configServerConfig, config, docker, metricReceiver, classLocking);
-        }
+        if (config.components.isEmpty()) {
+            dockerAdmin = Optional.of(new DockerAdminComponent(
+                    configServerConfig, config, docker, metricReceiver, classLocking));
+            enable(dockerAdmin.get());
+        } else {
+            logger.log(LogLevel.INFO, () -> {
+                String registeredComponentsList = adminRegistry
+                        .allComponentsById().keySet().stream()
+                        .map(ComponentId::stringValue)
+                        .collect(Collectors.joining(", "));
 
-        logger.log(LogLevel.INFO, () -> {
-            String registeredComponentsList = adminRegistry
-                    .allComponentsById().keySet().stream()
-                    .map(ComponentId::stringValue)
-                    .collect(Collectors.joining(", "));
-
-            return String.format(
-                    "Components registered = '%s', enabled = '%s'",
-                    registeredComponentsList,
-                    config.mainComponent);
-        });
-
-        AdminComponent component = adminRegistry.getComponent(config.mainComponent);
-        if (component == null) {
-            throw new IllegalArgumentException("There is no component named '" +
-                    config.mainComponent + "'");
+                String requestedComponentsList = config.components.stream()
+                        .collect(Collectors.joining(", "));
+
+                return String.format(
+                        "Components registered = '%s', enabled = '%s'",
+                        registeredComponentsList,
+                        requestedComponentsList);
+            });
+
+            for (String componentSpecificationString : config.components) {
+                AdminComponent component =
+                        adminRegistry.getComponent(componentSpecificationString);
+                if (component == null) {
+                    throw new IllegalArgumentException("There is no component named '" +
+                            componentSpecificationString + "'");
+                }
+                enable(component);
+            }
         }
+    }
 
-        return component;
+    private void enable(AdminComponent component) {
+        component.enable();
+        enabledComponents.add(component);
     }
 
     @Override
     public void close() {
-        if (mainAdminComponent != null) {
-            mainAdminComponent.disable();
-            mainAdminComponent = null;
+        int i = enabledComponents.size();
+        while (i --> 0) {
+            enabledComponents.remove(i).disable();
         }
     }
 
     public NodeAdminStateUpdater getNodeAdminStateUpdater() {
-        assert mainAdminComponent != null : "start() hasn't been called yet";
-        return mainAdminComponent.getNodeAdminStateUpdater();
+        return dockerAdmin.get().getNodeAdminStateUpdater();
     }
 }
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterImpl.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdater.java
index e4e66b57186..5ec041298fb 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterImpl.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdater.java
@@ -12,7 +12,6 @@ import com.yahoo.vespa.hosted.node.admin.nodeagent.NodeAttributes;
 import com.yahoo.vespa.hosted.node.admin.noderepository.NodeRepository;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.Orchestrator;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.OrchestratorException;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.node.admin.util.HttpException;
 import com.yahoo.vespa.hosted.provision.Node;
 
@@ -33,16 +32,16 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 import java.util.stream.Collectors;
 
-import static com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater.State.RESUMED;
-import static com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater.State.SUSPENDED_NODE_ADMIN;
-import static com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater.State.TRANSITIONING;
+import static com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater.State.RESUMED;
+import static com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater.State.SUSPENDED_NODE_ADMIN;
+import static com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater.State.TRANSITIONING;
 
 /**
  * Pulls information from node repository and forwards containers to run to node admin.
  *
  * @author dybis, stiankri
  */
-public class NodeAdminStateUpdaterImpl implements NodeAdminStateUpdater {
+public class NodeAdminStateUpdater {
     static final Duration FREEZE_CONVERGENCE_TIMEOUT = Duration.ofMinutes(5);
 
     private final AtomicBoolean terminated = new AtomicBoolean(false);
@@ -68,7 +67,7 @@ public class NodeAdminStateUpdaterImpl implements NodeAdminStateUpdater {
     private Optional<ClassLock> classLock;
     private Instant lastTick;
 
-    public NodeAdminStateUpdaterImpl(
+    public NodeAdminStateUpdater(
             NodeRepository nodeRepository,
             Orchestrator orchestrator,
             StorageMaintainer storageMaintainer,
@@ -112,7 +111,8 @@ public class NodeAdminStateUpdaterImpl implements NodeAdminStateUpdater {
         return this.getClass().getSimpleName() + "@" + Integer.toString(System.identityHashCode(this));
     }
 
-    @Override
+    public enum State { TRANSITIONING, RESUMED, SUSPENDED_NODE_ADMIN, SUSPENDED}
+
     public Map<String, Object> getDebugPage() {
         Map<String, Object> debug = new LinkedHashMap<>();
         synchronized (monitor) {
@@ -142,7 +142,6 @@ public class NodeAdminStateUpdaterImpl implements NodeAdminStateUpdater {
         }
     }
 
-    @Override
     public boolean setResumeStateAndCheckIfResumed(State wantedState) {
         synchronized (monitor) {
             if (this.wantedState != wantedState) {
@@ -310,7 +309,7 @@ public class NodeAdminStateUpdaterImpl implements NodeAdminStateUpdater {
 
         classLocking.interrupt();
 
-        // First we need to stop NodeAdminStateUpdaterImpl thread to make sure no new NodeAgents are spawned
+        // First we need to stop NodeAdminStateUpdater thread to make sure no new NodeAgents are spawned
         signalWorkToBeDone();
         specVerifierScheduler.shutdown();
 
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminProvider.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminProvider.java
index a5146fcae09..9a667c29fb3 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminProvider.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminProvider.java
@@ -7,9 +7,10 @@ import com.yahoo.concurrent.classlock.ClassLocking;
 import com.yahoo.container.di.componentgraph.Provider;
 import com.yahoo.vespa.hosted.dockerapi.Docker;
 import com.yahoo.vespa.hosted.dockerapi.metrics.MetricReceiverWrapper;
-import com.yahoo.vespa.hosted.node.admin.ConfigServerConfig;
 import com.yahoo.vespa.hosted.node.admin.component.AdminComponent;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminMain;
+import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater;
+import com.yahoo.vespa.hosted.node.admin.ConfigServerConfig;
 
 public class NodeAdminProvider implements Provider<NodeAdminStateUpdater> {
     private final NodeAdminMain nodeAdminMain;
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminStateUpdater.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminStateUpdater.java
deleted file mode 100644
index 755e1301c12..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/provider/NodeAdminStateUpdater.java
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.provider;
-
-import java.util.Map;
-
-public interface NodeAdminStateUpdater {
-    enum State { TRANSITIONING, RESUMED, SUSPENDED_NODE_ADMIN, SUSPENDED}
-
-    /**
-     * Set the wanted state, and return whether the current state equals it.
-     * Typically, this method should be called repeatedly until current state
-     * has converged.
-     */
-    boolean setResumeStateAndCheckIfResumed(State wantedState);
-
-    Map<String, Object> getDebugPage();
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/restapi/RestApiHandler.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/restapi/RestApiHandler.java
index a8dcde02ca6..03217c85329 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/restapi/RestApiHandler.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/restapi/RestApiHandler.java
@@ -6,9 +6,10 @@ import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.yahoo.container.jdisc.HttpRequest;
 import com.yahoo.container.jdisc.HttpResponse;
 import com.yahoo.container.jdisc.LoggingRequestHandler;
+import com.yahoo.container.logging.AccessLog;
 import com.yahoo.vespa.hosted.dockerapi.metrics.DimensionMetrics;
 import com.yahoo.vespa.hosted.dockerapi.metrics.MetricReceiverWrapper;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
+import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater;
 
 import javax.inject.Inject;
 import javax.ws.rs.core.MediaType;
@@ -16,6 +17,7 @@ import java.io.IOException;
 import java.io.OutputStream;
 import java.io.PrintStream;
 import java.nio.charset.StandardCharsets;
+import java.util.concurrent.Executor;
 
 import static com.yahoo.jdisc.http.HttpRequest.Method.GET;
 import static com.yahoo.jdisc.http.HttpRequest.Method.PUT;
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/AddYumRepo.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/AddYumRepoTask.java
index 9ca1c0286f9..a2ed6a80084 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/AddYumRepo.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/AddYumRepoTask.java
@@ -1,13 +1,11 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.task.util.yum;
-
-import com.yahoo.vespa.hosted.node.admin.component.TaskContext;
-import com.yahoo.vespa.hosted.node.admin.task.util.file.FileWriter;
+package com.yahoo.vespa.hosted.node.admin.task;
 
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.regex.Pattern;
 
-public class AddYumRepo {
+public class AddYumRepoTask implements Task {
     private static final Pattern REPOSITORY_ID_PATTERN = Pattern.compile("^[a-zA-Z_-]+$");
 
     private final String repositoryId; // e.g. "platform_rpms-latest"
@@ -15,10 +13,10 @@ public class AddYumRepo {
     private final String baseurl;
     private final boolean enabled;
 
-    public AddYumRepo(String repositoryId,
-                      String name,
-                      String baseurl,
-                      boolean enabled) {
+    public AddYumRepoTask(String repositoryId,
+                          String name,
+                          String baseurl,
+                          boolean enabled) {
         this.repositoryId = repositoryId;
         this.name = name;
         this.baseurl = baseurl;
@@ -26,18 +24,23 @@ public class AddYumRepo {
         validateRepositoryId(repositoryId);
     }
 
-    public boolean converge(TaskContext context) {
-        Path path = context.fileSystem().getPath("/etc/yum.repos.d",repositoryId + ".repo");
+    @Override
+    public boolean execute(TaskContext context) {
+        Path path = Paths.get("/etc/yum.repos.d",repositoryId + ".repo");
+
+        if (context.getFileSystem().isRegularFile(path)) {
+            return false;
+        }
 
-        FileWriter fileWriter = new FileWriter(path, this::getRepoFileContent)
+        WriteFileTask writeFileTask = new WriteFileTask(path, this::getRepoFileContent)
                 .withOwner("root")
                 .withGroup("root")
                 .withPermissions("rw-r--r--");
 
-        return fileWriter.converge(context);
+        return context.executeSubtask(writeFileTask);
     }
 
-    private String getRepoFileContent() {
+    String getRepoFileContent() {
         return String.join("\n",
                 "# This file was generated by node admin",
                 "# Do NOT modify this file by hand",
@@ -50,7 +53,7 @@ public class AddYumRepo {
         ) + "\n";
     }
 
-    private static void validateRepositoryId(String repositoryId) {
+    static void validateRepositoryId(String repositoryId) {
         if (!REPOSITORY_ID_PATTERN.matcher(repositoryId).matches()) {
             throw new IllegalArgumentException("Invalid repository ID '" + repositoryId + "'");
         }
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTask.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTask.java
new file mode 100644
index 00000000000..522abb81248
--- /dev/null
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTask.java
@@ -0,0 +1,49 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import com.yahoo.vespa.hosted.node.admin.io.FileSystem;
+
+import java.nio.file.Path;
+
+public class MakeDirectoryTask implements Task {
+    private final Path path;
+    private boolean withParents = false;
+
+    public MakeDirectoryTask(Path path) {
+        this.path = path;
+    }
+
+    public MakeDirectoryTask withParents() {
+        this.withParents = true;
+        return this;
+    }
+
+    Path getPath() {
+        return path;
+    }
+
+    boolean getWithParents() {
+        return withParents;
+    }
+
+    private boolean makeDirectory(FileSystem fileSystem,
+                                  Path directory,
+                                  boolean withParents) {
+        if (fileSystem.isDirectory(directory)) {
+            return false;
+        }
+
+        if (withParents) {
+            makeDirectory(fileSystem, directory.getParent(), withParents);
+        }
+
+        fileSystem.createDirectory(directory);
+
+        return true;
+    }
+
+    @Override
+    public boolean execute(TaskContext context) {
+        return makeDirectory(context.getFileSystem(), path, withParents);
+    }
+}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/Task.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/Task.java
new file mode 100644
index 00000000000..4d40ac02440
--- /dev/null
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/Task.java
@@ -0,0 +1,17 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import com.yahoo.vespa.hosted.node.admin.io.FileSystem;
+
+public interface Task {
+    interface TaskContext {
+        FileSystem getFileSystem();
+        boolean executeSubtask(Task task);
+    }
+
+    /**
+     * @return Returns false if task was a no-op. Used for informational purposes only.
+     * @throws RuntimeException if task could not be completed.
+     */
+    boolean execute(TaskContext context);
+}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTask.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTask.java
new file mode 100644
index 00000000000..308a7470d24
--- /dev/null
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTask.java
@@ -0,0 +1,80 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import com.yahoo.vespa.hosted.node.admin.io.FileSystemPath;
+import org.glassfish.jersey.internal.util.Producer;
+
+import java.nio.file.Path;
+import java.util.Optional;
+
+public class WriteFileTask implements Task {
+    private final Path path;
+    private final Producer<String> contentProducer;
+
+    private Optional<String> owner = Optional.empty();
+    private Optional<String> group = Optional.empty();
+    private Optional<String> permissions = Optional.empty();
+
+    public WriteFileTask(Path path, Producer<String> contentProducer) {
+        this.path = path;
+        this.contentProducer = contentProducer;
+    }
+
+    public WriteFileTask withOwner(String owner) {
+        this.owner = Optional.of(owner);
+        return this;
+    }
+
+    public WriteFileTask withGroup(String group) {
+        this.group = Optional.of(group);
+        return this;
+    }
+
+    /**
+     * @param permissions of the form "rwxr-x---".
+     */
+    public WriteFileTask withPermissions(String permissions) {
+        this.permissions = Optional.of(permissions);
+        return this;
+    }
+
+    @Override
+    public boolean execute(TaskContext context) {
+        final FileSystemPath fileSystemPath = context.getFileSystem().withPath(path);
+
+        // TODO: Only return false if content, permission, etc would be unchanged.
+        if (fileSystemPath.isRegularFile()) {
+            return false;
+        }
+
+        context.executeSubtask(new MakeDirectoryTask(path.getParent()).withParents());
+
+        String content = contentProducer.call();
+        fileSystemPath.writeUtf8File(content);
+        permissions.ifPresent(fileSystemPath::setPermissions);
+        owner.ifPresent(fileSystemPath::setOwner);
+        group.ifPresent(fileSystemPath::setGroup);
+
+        return true;
+    }
+
+    public Path getPath() {
+        return path;
+    }
+
+    public Producer<String> getContentProducer() {
+        return contentProducer;
+    }
+
+    public Optional<String> getOwner() {
+        return owner;
+    }
+
+    public Optional<String> getGroup() {
+        return group;
+    }
+
+    public Optional<String> getPermissions() {
+        return permissions;
+    }
+}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/package-info.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/package-info.java
index 3c5292982d0..433884139f6 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/package-info.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/package-info.java
@@ -1,5 +1,5 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 @ExportPackage
-package com.yahoo.vespa.hosted.node.admin.task.util.yum;
+package com.yahoo.vespa.hosted.node.admin.task;
 
 import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriter.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriter.java
deleted file mode 100644
index 60a7b3482b2..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriter.java
+++ /dev/null
@@ -1,61 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import com.yahoo.vespa.hosted.node.admin.component.TaskContext;
-import org.glassfish.jersey.internal.util.Producer;
-
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.Optional;
-import java.util.logging.Logger;
-
-public class FileWriter {
-    private static final Logger logger = Logger.getLogger(FileWriter.class.getName());
-
-    private final Path path;
-    private final Producer<String> contentProducer;
-
-    private Optional<String> owner = Optional.empty();
-    private Optional<String> group = Optional.empty();
-    private Optional<String> permissions = Optional.empty();
-
-    public FileWriter(Path path, Producer<String> contentProducer) {
-        this.path = path;
-        this.contentProducer = contentProducer;
-    }
-
-    public FileWriter withOwner(String owner) {
-        this.owner = Optional.of(owner);
-        return this;
-    }
-
-    public FileWriter withGroup(String group) {
-        this.group = Optional.of(group);
-        return this;
-    }
-
-    public FileWriter withPermissions(String permissions) {
-        this.permissions = Optional.of(permissions);
-        return this;
-    }
-
-    public boolean converge(TaskContext context) {
-        // TODO: Only return false if content, permission, etc would be unchanged.
-        if (Files.isRegularFile(path)) {
-            return false;
-        }
-
-        context.logSystemModification(logger,"Writing file " + path);
-
-        String content = contentProducer.call();
-
-        UnixPath unixPath = new UnixPath(path);
-        unixPath.createParents();
-        unixPath.writeUtf8File(content);
-        permissions.ifPresent(unixPath::setPermissions);
-        owner.ifPresent(unixPath::setOwner);
-        group.ifPresent(unixPath::setGroup);
-
-        return true;
-    }
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/IOExceptionUtil.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/IOExceptionUtil.java
deleted file mode 100644
index dee5525d42a..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/IOExceptionUtil.java
+++ /dev/null
@@ -1,34 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import java.io.IOException;
-import java.io.UncheckedIOException;
-
-public class IOExceptionUtil {
-    public static <T> void uncheck(RunnableThrowingIOException<T> runnable) {
-        try {
-            runnable.run();
-        } catch (IOException e) {
-            throw new UncheckedIOException(e);
-        }
-    }
-
-    public static <T> T uncheck(SupplierThrowingIOException<T> supplier) {
-        try {
-            return supplier.get();
-        } catch (IOException e) {
-            throw new UncheckedIOException(e);
-        }
-    }
-
-    @FunctionalInterface
-    public interface SupplierThrowingIOException<T> {
-        T get() throws IOException;
-    }
-
-
-    @FunctionalInterface
-    public interface RunnableThrowingIOException<T> {
-        void run() throws IOException;
-    }
-}
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/package-info.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/package-info.java
deleted file mode 100644
index 076912c073d..00000000000
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/package-info.java
+++ /dev/null
@@ -1,5 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-@ExportPackage
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/node-admin/src/main/sh/node-admin.sh b/node-admin/src/main/sh/node-admin.sh
index 3196ff9fa32..ff0ea492318 100755
--- a/node-admin/src/main/sh/node-admin.sh
+++ b/node-admin/src/main/sh/node-admin.sh
@@ -67,19 +67,16 @@ EOF
     exit 1
 }
 
-if (( $# == 0 )); then
+if (( $# != 1 )); then
     Usage
 fi
 
-command="$1"
-shift
-
-case "$command" in
+case "$1" in
     start)
-	"$VESPA_HOME"/libexec/vespa/standalone-container.sh start -s node-admin -u root "$@"
+	"$VESPA_HOME"/libexec/vespa/standalone-container.sh start -s node-admin -u root
 	;;
     stop)
-	"$VESPA_HOME"/libexec/vespa/standalone-container.sh stop -s node-admin -u root "$@"
+	"$VESPA_HOME"/libexec/vespa/standalone-container.sh stop -s node-admin -u root
 	;;
     *) Usage ;;
 esac
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/DockerTester.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/DockerTester.java
index 3cfc67824ed..7a314ff0614 100644
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/DockerTester.java
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/DockerTester.java
@@ -11,7 +11,7 @@ import com.yahoo.vespa.hosted.node.admin.docker.DockerOperationsImpl;
 import com.yahoo.vespa.hosted.node.admin.maintenance.acl.AclMaintainer;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdmin;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminImpl;
-import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdaterImpl;
+import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.node.admin.nodeagent.NodeAgent;
 import com.yahoo.vespa.hosted.node.admin.nodeagent.NodeAgentImpl;
 import com.yahoo.vespa.hosted.node.admin.util.Environment;
@@ -40,7 +40,7 @@ public class DockerTester implements AutoCloseable {
     final CallOrderVerifier callOrderVerifier = new CallOrderVerifier();
     final Docker dockerMock = new DockerMock(callOrderVerifier);
     final NodeRepoMock nodeRepositoryMock = new NodeRepoMock(callOrderVerifier);
-    final NodeAdminStateUpdaterImpl nodeAdminStateUpdater;
+    final NodeAdminStateUpdater nodeAdminStateUpdater;
     final NodeAdmin nodeAdmin;
     private final OrchestratorMock orchestratorMock = new OrchestratorMock(callOrderVerifier);
 
@@ -66,7 +66,7 @@ public class DockerTester implements AutoCloseable {
         Function<String, NodeAgent> nodeAgentFactory = (hostName) -> new NodeAgentImpl(hostName, nodeRepositoryMock,
                 orchestratorMock, dockerOperations, storageMaintainer, aclMaintainer, environment, clock, NODE_AGENT_SCAN_INTERVAL);
         nodeAdmin = new NodeAdminImpl(dockerOperations, nodeAgentFactory, storageMaintainer, aclMaintainer, mr, Clock.systemUTC());
-        nodeAdminStateUpdater = new NodeAdminStateUpdaterImpl(nodeRepositoryMock, orchestratorMock, storageMaintainer,
+        nodeAdminStateUpdater = new NodeAdminStateUpdater(nodeRepositoryMock, orchestratorMock, storageMaintainer,
                 nodeAdmin, "basehostname", clock, NODE_ADMIN_CONVERGE_STATE_INTERVAL, new ClassLocking());
         nodeAdminStateUpdater.start();
     }
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RebootTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RebootTest.java
index 2db93ba4203..0b5d67dd13c 100644
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RebootTest.java
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RebootTest.java
@@ -5,8 +5,7 @@ import com.yahoo.vespa.hosted.dockerapi.DockerImage;
 import com.yahoo.vespa.hosted.node.admin.ContainerNodeSpec;
 import com.yahoo.vespa.hosted.node.admin.docker.DockerOperationsImpl;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdmin;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
-import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdaterImpl;
+import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.provision.Node;
 import org.junit.Ignore;
 import org.junit.Test;
@@ -42,7 +41,7 @@ public class RebootTest {
                     "createContainerCommand with DockerImage { imageId=dockerImage }, HostName: host1.test.yahoo.com, ContainerName { name=host1 }",
                     "updateNodeAttributes with HostName: host1.test.yahoo.com, NodeAttributes{restartGeneration=1, rebootGeneration=null,  dockerImage=dockerImage, vespaVersion='null'}");
 
-            NodeAdminStateUpdaterImpl updater = dockerTester.nodeAdminStateUpdater;
+            NodeAdminStateUpdater updater = dockerTester.nodeAdminStateUpdater;
             assertThat(updater.setResumeStateAndCheckIfResumed(NodeAdminStateUpdater.State.SUSPENDED),
                        is(Optional.of("Not all node agents are frozen.")));
 
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RunInContainerTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RunInContainerTest.java
index a0e122d99fc..23d55bd947c 100644
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RunInContainerTest.java
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/integrationTests/RunInContainerTest.java
@@ -15,8 +15,7 @@ import com.yahoo.vespa.hosted.node.admin.maintenance.StorageMaintainer;
 import com.yahoo.vespa.hosted.node.admin.maintenance.acl.AclMaintainer;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdmin;
 import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminImpl;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
-import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdaterImpl;
+import com.yahoo.vespa.hosted.node.admin.nodeadmin.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.node.admin.nodeagent.NodeAgent;
 import com.yahoo.vespa.hosted.node.admin.nodeagent.NodeAgentImpl;
 import com.yahoo.vespa.hosted.node.admin.noderepository.NodeRepository;
@@ -78,7 +77,7 @@ public class RunInContainerTest {
 
     @Before
     public void startContainer() throws Exception {
-        // To test the initial NodeAdminStateUpdaterImpl convergence towards RESUME, orchestrator should
+        // To test the initial NodeAdminStateUpdater convergence towards RESUME, orchestrator should
         // deny permission to resume for parent host, otherwise it'll converge to RESUME before REST
         // handler comes up
         doThrow(new RuntimeException()).when(orchestratorMock).resume(parentHostname);
@@ -242,7 +241,7 @@ public class RunInContainerTest {
                 (hostName) -> new NodeAgentImpl(hostName, nodeRepositoryMock, orchestratorMock, dockerOperationsMock,
                         storageMaintainer, aclMaintainer, environment, Clock.systemUTC(), NODE_AGENT_SCAN_INTERVAL);
         private final NodeAdmin nodeAdmin = new NodeAdminImpl(dockerOperationsMock, nodeAgentFactory, storageMaintainer, aclMaintainer, mr, Clock.systemUTC());
-        private final NodeAdminStateUpdaterImpl nodeAdminStateUpdater = new NodeAdminStateUpdaterImpl(nodeRepositoryMock,
+        private final NodeAdminStateUpdater nodeAdminStateUpdater = new NodeAdminStateUpdater(nodeRepositoryMock,
                 orchestratorMock, storageMaintainer, nodeAdmin, "localhost.test.yahoo.com", Clock.systemUTC(), NODE_ADMIN_CONVERGE_STATE_INTERVAL, new ClassLocking());
 
         public NodeAdminProviderWithMocks() {
@@ -250,7 +249,7 @@ public class RunInContainerTest {
         }
 
         @Override
-        public NodeAdminStateUpdaterImpl get() {
+        public NodeAdminStateUpdater get() {
             return nodeAdminStateUpdater;
         }
 
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemTest.java
new file mode 100644
index 00000000000..6961efc159c
--- /dev/null
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/io/FileSystemTest.java
@@ -0,0 +1,81 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.io;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.nio.file.Path;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class FileSystemTest {
+    @Rule
+    public final TemporaryFolder folder = new TemporaryFolder();
+
+    private Path root;
+    private Path path;
+
+    private final FileSystem fileSystem = new FileSystem();
+
+    @Before
+    public void setUp() throws Exception {
+        root = folder.getRoot().toPath();
+        path = folder.newFile().toPath();
+    }
+
+    @Test
+    public void isDirectory() throws Exception {
+        assertTrue(fileSystem.isDirectory(root));
+        assertFalse(fileSystem.isDirectory(path));
+    }
+
+    @Test
+    public void isRegularFile() throws Exception {
+        assertTrue(fileSystem.isRegularFile(path));
+        assertFalse(fileSystem.isRegularFile(root));
+    }
+
+    @Test
+    public void createDirectory() throws Exception {
+        Path dir = root.resolve("subdir");
+        fileSystem.createDirectory(dir);
+        assertTrue(fileSystem.isDirectory(dir));
+    }
+
+    @Test
+    public void utf8FileIO() throws Exception {
+        String original = "foo\nbar\n";
+        Path path = root.resolve("example.txt");
+        fileSystem.writeUtf8File(path, original);
+        String fromFile = fileSystem.readUtf8File(path);
+        assertEquals(original, fromFile);
+    }
+
+    @Test
+    public void permissions() throws Exception {
+        String expectedPermissions = "rwxr-x---";
+        fileSystem.setPermissions(path, expectedPermissions);
+        assertEquals(expectedPermissions, fileSystem.getPermissions(path));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badPermissionsString() {
+        fileSystem.setPermissions(path, "abcdefghi");
+    }
+
+    @Test
+    public void owner() throws Exception {
+        String owner = fileSystem.getOwner(path);
+        fileSystem.setOwner(path, owner);
+    }
+
+    @Test
+    public void group() throws Exception {
+        String group = fileSystem.getGroup(path);
+        fileSystem.setGroup(path, group);
+    }
+}
\ No newline at end of file
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterImplTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterTest.java
index 7920d0cad29..1058278a02c 100644
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterImplTest.java
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminStateUpdaterTest.java
@@ -7,7 +7,6 @@ import com.yahoo.vespa.hosted.node.admin.maintenance.StorageMaintainer;
 import com.yahoo.vespa.hosted.node.admin.noderepository.NodeRepository;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.Orchestrator;
 import com.yahoo.vespa.hosted.node.admin.orchestrator.OrchestratorException;
-import com.yahoo.vespa.hosted.node.admin.provider.NodeAdminStateUpdater;
 import com.yahoo.vespa.hosted.provision.Node;
 import org.junit.Test;
 
@@ -33,11 +32,11 @@ import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.when;
 
 /**
- * Basic test of NodeAdminStateUpdaterImpl
+ * Basic test of NodeAdminStateUpdater
  *
  * @author freva
  */
-public class NodeAdminStateUpdaterImplTest {
+public class NodeAdminStateUpdaterTest {
     private final NodeRepository nodeRepository = mock(NodeRepository.class);
     private final Orchestrator orchestrator = mock(Orchestrator.class);
     private final StorageMaintainer storageMaintainer = mock(StorageMaintainer.class);
@@ -46,7 +45,7 @@ public class NodeAdminStateUpdaterImplTest {
     private final ManualClock clock = new ManualClock();
     private final Duration convergeStateInterval = Duration.ofSeconds(30);
 
-    private final NodeAdminStateUpdaterImpl refresher = spy(new NodeAdminStateUpdaterImpl(
+    private final NodeAdminStateUpdater refresher = spy(new NodeAdminStateUpdater(
             nodeRepository, orchestrator, storageMaintainer, nodeAdmin, parentHostname, clock, convergeStateInterval, null));
 
 
@@ -103,7 +102,7 @@ public class NodeAdminStateUpdaterImplTest {
         // The second orchestration failure happens after the freeze convergence timeout,
         // and so SHOULD call setFrozen(false)
         when(nodeAdmin.setFrozen(eq(true))).thenReturn(true);
-        when(nodeAdmin.subsystemFreezeDuration()).thenReturn(NodeAdminStateUpdaterImpl.FREEZE_CONVERGENCE_TIMEOUT.plusMinutes(1));
+        when(nodeAdmin.subsystemFreezeDuration()).thenReturn(NodeAdminStateUpdater.FREEZE_CONVERGENCE_TIMEOUT.plusMinutes(1));
         doThrow(new RuntimeException("Cannot allow to suspend because some reason")).doNothing()
                 .when(orchestrator).suspend(eq(parentHostname));
         tickAfter(35);
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/AddYumRepoTaskTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/AddYumRepoTaskTest.java
new file mode 100644
index 00000000000..3e444f08508
--- /dev/null
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/AddYumRepoTaskTest.java
@@ -0,0 +1,70 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import org.junit.Test;
+import org.mockito.ArgumentCaptor;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+public class AddYumRepoTaskTest extends TaskTestBase {
+    private Path expectedPath;
+    private String expectedContent;
+    private AddYumRepoTask task;
+
+    public void setUp() {
+        String repository = "repo-id";
+        String name = "name";
+        String baseUrl = "base-url";
+        boolean enabled = true;
+        expectedContent = "# This file was generated by node admin\n" +
+                "# Do NOT modify this file by hand\n" +
+                "\n" +
+                "[repo-id]\n" +
+                "name=name\n" +
+                "baseurl=base-url\n" +
+                "enabled=1\n" +
+                "gpgcheck=0\n";
+
+        task = new AddYumRepoTask(repository, name, baseUrl, enabled);
+        expectedPath = Paths.get("/etc/yum.repos.d/" + repository + ".repo");
+    }
+
+    @Test
+    public void alreadyExistsIsNoOp() {
+        when(fileSystemMock.isRegularFile(expectedPath)).thenReturn(true);
+        assertFalse(task.execute(contextMock));
+    }
+
+    @Test
+    public void fileContent() {
+        assertEquals(expectedContent, task.getRepoFileContent());
+    }
+
+    @Test
+    public void createsFile() {
+        when(fileSystemMock.isRegularFile(expectedPath)).thenReturn(false);
+       when(contextMock.executeSubtask(any())).thenReturn(true);
+        assertTrue(task.execute(contextMock));
+
+        // Writing a file with the expected content
+        ArgumentCaptor<WriteFileTask> writeFileTaskArgumentCaptor =
+                ArgumentCaptor.forClass(WriteFileTask.class);
+        verify(contextMock, times(1))
+                .executeSubtask(writeFileTaskArgumentCaptor.capture());
+        WriteFileTask writeFileTask = writeFileTaskArgumentCaptor.getValue();
+        assertEquals(expectedPath, writeFileTask.getPath());
+        assertEquals(expectedContent, writeFileTask.getContentProducer().call());
+        assertEquals("rw-r--r--", writeFileTask.getPermissions().get());
+        assertEquals("root", writeFileTask.getOwner().get());
+        assertEquals("root", writeFileTask.getGroup().get());
+    }
+}
\ No newline at end of file
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTaskTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTaskTest.java
new file mode 100644
index 00000000000..cb4d8ab677c
--- /dev/null
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/MakeDirectoryTaskTest.java
@@ -0,0 +1,49 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import com.yahoo.vespa.hosted.node.admin.io.FileSystem;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.InOrder;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class MakeDirectoryTaskTest {
+    private final FileSystem fileSystem = mock(FileSystem.class);
+    private final Task.TaskContext context = mock(Task.TaskContext.class);
+    private final Path root = Paths.get("/");
+    private final Path fooDir = root.resolve("foo");
+    private final Path barDir = fooDir.resolve("bar");
+    private final MakeDirectoryTask task = new MakeDirectoryTask(barDir);
+
+    @Before
+    public void setUp() {
+        when(context.getFileSystem()).thenReturn(fileSystem);
+    }
+
+    @Test
+    public void directoryExists() {
+        when(fileSystem.isDirectory(barDir)).thenReturn(true);
+        assertFalse(task.execute(context));
+    }
+
+    @Test
+    public void withParents() {
+        when(fileSystem.isDirectory(barDir)).thenReturn(false);
+        when(fileSystem.isDirectory(fooDir)).thenReturn(false);
+        when(fileSystem.isDirectory(root)).thenReturn(true);
+        assertTrue(task.withParents().execute(context));
+
+        InOrder inOrder = inOrder(fileSystem);
+        inOrder.verify(fileSystem).createDirectory(fooDir);
+        inOrder.verify(fileSystem).createDirectory(barDir);
+        inOrder.verifyNoMoreInteractions();
+    }
+}
\ No newline at end of file
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/TaskTestBase.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/TaskTestBase.java
new file mode 100644
index 00000000000..ac24ac6524e
--- /dev/null
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/TaskTestBase.java
@@ -0,0 +1,26 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import com.yahoo.vespa.hosted.node.admin.io.FileSystem;
+import org.junit.Before;
+
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+abstract class TaskTestBase {
+    protected final FileSystem fileSystemMock = mock(FileSystem.class);
+    protected final Task.TaskContext contextMock = mock(Task.TaskContext.class);
+
+    @Before
+    public void baseSetup() {
+        when(contextMock.getFileSystem()).thenReturn(fileSystemMock);
+        when(fileSystemMock.withPath(any())).thenCallRealMethod();
+        setUp();
+    }
+
+    /**
+     * Override this to set up before each test.
+     */
+    void setUp() {}
+}
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTaskTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTaskTest.java
new file mode 100644
index 00000000000..9c998cc6fdb
--- /dev/null
+++ b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/WriteFileTaskTest.java
@@ -0,0 +1,80 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task;
+
+import org.glassfish.jersey.internal.util.Producer;
+import org.junit.Test;
+import org.mockito.ArgumentCaptor;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+public class WriteFileTaskTest extends TaskTestBase {
+    private final String content = "line1\nline2\n";
+
+    @Test
+    public void testWrite() {
+        Path parentDirectory = Paths.get("/foo");
+        Path path = parentDirectory.resolve("bar");
+
+        @SuppressWarnings("unchecked")
+        Producer<String> contentProducer = (Producer<String>) mock(Producer.class);
+        when(contentProducer.call()).thenReturn(content);
+
+        final String permissions = "rwxr-x---";
+        final String owner = "owner";
+        final String group = "group";
+
+        WriteFileTask task = new WriteFileTask(path, contentProducer)
+                .withPermissions(permissions)
+                .withOwner(owner)
+                .withGroup(group);
+
+        when(fileSystemMock.isRegularFile(path)).thenReturn(false);
+        when(contextMock.executeSubtask(any(MakeDirectoryTask.class))).thenReturn(false);
+
+        assertTrue(task.execute(contextMock));
+
+        verify(contentProducer, times(1)).call();
+        verify(fileSystemMock).writeUtf8File(path, content);
+        verify(fileSystemMock).setPermissions(path, permissions);
+        verify(fileSystemMock).setOwner(path, owner);
+        verify(fileSystemMock).setGroup(path, group);
+
+        // Writing a file with the expected content
+        ArgumentCaptor<MakeDirectoryTask> makeDirectoryTaskCaptor =
+                ArgumentCaptor.forClass(MakeDirectoryTask.class);
+        verify(contextMock, times(1))
+                .executeSubtask(makeDirectoryTaskCaptor.capture());
+
+        MakeDirectoryTask makeDirectoryTask = makeDirectoryTaskCaptor.getValue();
+        assertEquals(parentDirectory, makeDirectoryTask.getPath());
+        assertTrue(makeDirectoryTask.getWithParents());
+    }
+
+    @Test
+    public void fileAlreadyExists() {
+        Path path = Paths.get("foo");
+
+        final String permissions = "rwxr-x---";
+        final String owner = "owner";
+        final String group = "group";
+
+        WriteFileTask task = new WriteFileTask(path, () -> content)
+                .withPermissions(permissions)
+                .withOwner(owner)
+                .withGroup(group);
+
+        when(fileSystemMock.isRegularFile(path)).thenReturn(true);
+
+        assertFalse(task.execute(contextMock));
+   }
+}
\ No newline at end of file
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriterTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriterTest.java
deleted file mode 100644
index ca4eabf855b..00000000000
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileWriterTest.java
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import com.yahoo.vespa.hosted.node.admin.component.TaskContext;
-import org.junit.Test;
-
-import java.nio.file.FileSystem;
-import java.nio.file.Path;
-import java.time.Instant;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.mockito.Matchers.any;
-import static org.mockito.Matchers.eq;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.times;
-import static org.mockito.Mockito.verify;
-
-public class FileWriterTest {
-    private final FileSystem fileSystem = TestFileSystem.create();
-
-    @Test
-    public void testWrite() {
-        final String content = "content";
-        final String permissions = "rwxr-xr-x";
-        final String owner = "owner";
-        final String group = "group";
-
-        Path path = fileSystem.getPath("/opt/vespa/tmp/file.txt");
-        FileWriter writer = new FileWriter(path, () -> content)
-                .withPermissions(permissions)
-                .withOwner(owner)
-                .withGroup(group);
-        TaskContext context = mock(TaskContext.class);
-        assertTrue(writer.converge(context));
-        verify(context, times(1)).logSystemModification(any(), eq("Writing file " + path));
-
-        UnixPath unixPath = new UnixPath(path);
-        assertEquals(content, unixPath.readUtf8File());
-        assertEquals(permissions, unixPath.getPermissions());
-        assertEquals(owner, unixPath.getOwner());
-        assertEquals(group, unixPath.getGroup());
-        Instant fileTime = unixPath.getLastModifiedTime();
-
-        // Second time is a no-op.
-        assertFalse(writer.converge(context));
-        assertEquals(fileTime, unixPath.getLastModifiedTime());
-    }
-}
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/TestFileSystem.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/TestFileSystem.java
deleted file mode 100644
index 465cb671a97..00000000000
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/TestFileSystem.java
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import com.google.common.jimfs.Configuration;
-import com.google.common.jimfs.Feature;
-import com.google.common.jimfs.Jimfs;
-import com.google.common.jimfs.PathType;
-
-import java.nio.file.FileSystem;
-
-public class TestFileSystem {
-    public static FileSystem create() {
-        // This configuration is based on Configuration.unix(), except:
-        //  - Use "posix" attribute view which is necessary for permissions, owner, and group.
-        Configuration configuration = Configuration.builder(PathType.unix())
-                .setRoots("/")
-                .setWorkingDirectory("/work")
-                .setAttributeViews("posix")
-                .setSupportedFeatures(Feature.LINKS, Feature.SYMBOLIC_LINKS, Feature.SECURE_DIRECTORY_STREAM, Feature.FILE_CHANNEL)
-                .build();
-        return Jimfs.newFileSystem(configuration);
-    }
-}
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/UnixPathTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/UnixPathTest.java
deleted file mode 100644
index 821c6397ee7..00000000000
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/file/UnixPathTest.java
+++ /dev/null
@@ -1,65 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-package com.yahoo.vespa.hosted.node.admin.task.util.file;
-
-import org.junit.Test;
-
-import java.nio.file.FileSystem;
-import java.nio.file.Files;
-import java.nio.file.Path;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
-public class UnixPathTest {
-    final FileSystem fileSystem = TestFileSystem.create();
-
-    @Test
-    public void createParents() throws Exception {
-        Path parentDirectory = fileSystem.getPath("/a/b/c");
-        Path filePath = parentDirectory.resolve("bar");
-        UnixPath path = new UnixPath(filePath);
-
-        assertFalse(Files.exists(fileSystem.getPath("/a")));
-        path.createParents();
-        assertTrue(Files.exists(parentDirectory));
-    }
-
-    @Test
-    public void utf8File() throws Exception {
-        String original = "foo\nbar\n";
-        UnixPath path = new UnixPath(fileSystem.getPath("example.txt"));
-        path.writeUtf8File(original);
-        String fromFile = path.readUtf8File();
-        assertEquals(original, fromFile);
-    }
-
-    @Test
-    public void permissions() throws Exception {
-        String expectedPermissions = "rwxr-x---";
-        UnixPath path = new UnixPath(fileSystem.getPath("file.txt"));
-        path.writeUtf8File("foo");
-        path.setPermissions(expectedPermissions);
-        assertEquals(expectedPermissions, path.getPermissions());
-    }
-
-    @Test(expected = IllegalArgumentException.class)
-    public void badPermissionsString() {
-        new UnixPath(fileSystem.getPath("file.txt")).setPermissions("abcdefghi");
-    }
-
-    @Test
-    public void owner() throws Exception {
-        FileSystem fs = TestFileSystem.create();
-        Path path = fs.getPath("file.txt");
-        UnixPath unixPath = new UnixPath(path);
-        unixPath.writeUtf8File("foo");
-
-        unixPath.setOwner("owner");
-        assertEquals("owner", unixPath.getOwner());
-
-        unixPath.setGroup("group");
-        assertEquals("group", unixPath.getGroup());
-    }
-}
diff --git a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/AddYumRepoTest.java b/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/AddYumRepoTest.java
deleted file mode 100644
index 7b6ab91345b..00000000000
--- a/node-admin/src/test/java/com/yahoo/vespa/hosted/node/admin/task/util/yum/AddYumRepoTest.java
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-package com.yahoo.vespa.hosted.node.admin.task.util.yum;
-
-import com.yahoo.vespa.hosted.node.admin.component.TaskContext;
-import com.yahoo.vespa.hosted.node.admin.task.util.file.TestFileSystem;
-import com.yahoo.vespa.hosted.node.admin.task.util.file.UnixPath;
-import org.junit.Test;
-
-import java.nio.file.FileSystem;
-import java.time.Instant;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
-
-public class AddYumRepoTest {
-    @Test
-    public void converge() throws Exception {
-        String repositoryId = "repoid";
-        String name = "name";
-        String baseurl = "http://foo.com/bar";
-        boolean enabled = true;
-
-        AddYumRepo addYumRepo = new AddYumRepo(
-                repositoryId,
-                name,
-                baseurl,
-                enabled);
-
-        TaskContext context = mock(TaskContext.class);
-
-        FileSystem fileSystem = TestFileSystem.create();
-        when(context.fileSystem()).thenReturn(fileSystem);
-
-        assertTrue(addYumRepo.converge(context));
-
-        UnixPath unixPath = new UnixPath(fileSystem.getPath("/etc/yum.repos.d/" + repositoryId + ".repo"));
-        String content = unixPath.readUtf8File();
-        assertEquals("# This file was generated by node admin\n" +
-                "# Do NOT modify this file by hand\n" +
-                "\n" +
-                "[repoid]\n" +
-                "name=name\n" +
-                "baseurl=http://foo.com/bar\n" +
-                "enabled=1\n" +
-                "gpgcheck=0\n", content);
-        Instant lastModifiedTime = unixPath.getLastModifiedTime();
-
-        // Second time is a no-op
-        assertFalse(addYumRepo.converge(context));
-        assertEquals(lastModifiedTime, unixPath.getLastModifiedTime());
-    }
-
-}
\ No newline at end of file