Store config change actions on prepare, trigger on activate

13 files changed, 220 insertions, 56 deletions

diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/Deployment.java b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/Deployment.java
index ae1215fd5aa..f10bea5da6e 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/Deployment.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/Deployment.java
@@ -23,6 +23,9 @@ import com.yahoo.vespa.config.server.application.ConfigNotConvergedException;
 import com.yahoo.vespa.config.server.configchange.ConfigChangeActions;
 import com.yahoo.vespa.config.server.configchange.ReindexActions;
 import com.yahoo.vespa.config.server.configchange.RestartActions;
+import com.yahoo.vespa.config.server.session.ActivationTriggers;
+import com.yahoo.vespa.config.server.session.ActivationTriggers.NodeRestart;
+import com.yahoo.vespa.config.server.session.ActivationTriggers.Reindexing;
 import com.yahoo.vespa.config.server.session.PrepareParams;
 import com.yahoo.vespa.config.server.session.Session;
 import com.yahoo.vespa.config.server.session.SessionRepository;
@@ -31,6 +34,7 @@ import com.yahoo.yolean.concurrent.Memoized;
 
 import java.time.Clock;
 import java.time.Duration;
+import java.util.List;
 import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicReference;
@@ -41,6 +45,7 @@ import java.util.stream.Collectors;
 
 import static com.yahoo.vespa.config.server.application.ConfigConvergenceChecker.ServiceListResponse;
 import static com.yahoo.vespa.config.server.session.Session.Status.DELETE;
+import static java.util.stream.Collectors.toSet;
 
 /**
  * The process of deploying an application.
@@ -63,14 +68,12 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
     private final Tenant tenant;
     private final DeployLogger deployLogger;
     private final Clock clock;
-    private final boolean internalRedeploy;
 
     private boolean prepared;
     private ConfigChangeActions configChangeActions;
 
     private Deployment(Session session, ApplicationRepository applicationRepository, Supplier<PrepareParams> params,
-                       Optional<Provisioner> provisioner, Tenant tenant, DeployLogger deployLogger, Clock clock,
-                       boolean internalRedeploy, boolean prepared) {
+                       Optional<Provisioner> provisioner, Tenant tenant, DeployLogger deployLogger, Clock clock, boolean prepared) {
         this.session = session;
         this.applicationRepository = applicationRepository;
         this.params = params;
@@ -78,27 +81,26 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
         this.tenant = tenant;
         this.deployLogger = deployLogger;
         this.clock = clock;
-        this.internalRedeploy = internalRedeploy;
         this.prepared = prepared;
     }
 
     public static Deployment unprepared(Session session, ApplicationRepository applicationRepository,
                                         Optional<Provisioner> provisioner, Tenant tenant, PrepareParams params, DeployLogger logger, Clock clock) {
-        return new Deployment(session, applicationRepository, () -> params, provisioner, tenant, logger, clock, false, false);
+        return new Deployment(session, applicationRepository, () -> params, provisioner, tenant, logger, clock, false);
     }
 
     public static Deployment unprepared(Session session, ApplicationRepository applicationRepository,
                                         Optional<Provisioner> provisioner, Tenant tenant, DeployLogger logger,
                                         Duration timeout, Clock clock, boolean validate, boolean isBootstrap) {
-        Supplier<PrepareParams> params = createPrepareParams(clock, timeout, session, isBootstrap, !validate, false, true);
-        return new Deployment(session, applicationRepository, params, provisioner, tenant, logger, clock, true, false);
+        Supplier<PrepareParams> params = createPrepareParams(clock, timeout, session, true, isBootstrap, !validate, false, true);
+        return new Deployment(session, applicationRepository, params, provisioner, tenant, logger, clock, false);
     }
 
     public static Deployment prepared(Session session, ApplicationRepository applicationRepository,
                                       Optional<Provisioner> provisioner, Tenant tenant, DeployLogger logger,
                                       Duration timeout, Clock clock, boolean isBootstrap, boolean force) {
-        Supplier<PrepareParams> params = createPrepareParams(clock, timeout, session, isBootstrap, false, force, false);
-        return new Deployment(session, applicationRepository, params, provisioner, tenant, logger, clock, false, true);
+        Supplier<PrepareParams> params = createPrepareParams(clock, timeout, session, false, isBootstrap, false, force, false);
+        return new Deployment(session, applicationRepository, params, provisioner, tenant, logger, clock, true);
     }
 
     /** Prepares this. This does nothing if this is already prepared */
@@ -106,9 +108,8 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
     public void prepare() {
         if (prepared) return;
 
-        PrepareParams params = this.params.get();
-        try (ActionTimer timer = applicationRepository.timerFor(params.getApplicationId(), ConfigServerMetrics.DEPLOYMENT_PREPARE_MILLIS.baseName())) {
-            this.configChangeActions = sessionRepository().prepareLocalSession(session, deployLogger, params, clock.instant());
+        try (ActionTimer timer = applicationRepository.timerFor(params.get().getApplicationId(), ConfigServerMetrics.DEPLOYMENT_PREPARE_MILLIS.baseName())) {
+            this.configChangeActions = sessionRepository().prepareLocalSession(session, deployLogger, params.get(), clock.instant());
             this.prepared = true;
         } catch (Exception e) {
             log.log(Level.FINE, "Preparing session " + session.getSessionId() + " failed, deleting it");
@@ -124,18 +125,17 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
 
         validateSessionStatus(session);
 
-        PrepareParams params = this.params.get();
-        waitForResourcesOrTimeout(params, session, provisioner);
+        waitForResourcesOrTimeout(params.get(), session, provisioner);
 
         ApplicationId applicationId = session.getApplicationId();
         try (ActionTimer timer = applicationRepository.timerFor(applicationId, ConfigServerMetrics.DEPLOYMENT_ACTIVATE_MILLIS.baseName())) {
-            TimeoutBudget timeoutBudget = params.getTimeoutBudget();
+            TimeoutBudget timeoutBudget = params.get().getTimeoutBudget();
             timeoutBudget.assertNotTimedOut(() -> "Timeout exceeded when trying to activate '" + applicationId + "'");
 
-            Activation activation = applicationRepository.activate(session, applicationId, tenant, params.force());
+            Activation activation = applicationRepository.activate(session, applicationId, tenant, params.get().force());
             waitForActivation(applicationId, timeoutBudget, activation);
             restartServicesIfNeeded(applicationId);
-            storeReindexing(applicationId, session.getMetaData().getGeneration());
+            storeReindexing(applicationId);
 
             return session.getMetaData().getGeneration();
         }
@@ -166,19 +166,22 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
     }
 
     private void restartServicesIfNeeded(ApplicationId applicationId) {
-        if (provisioner.isEmpty() || configChangeActions == null) return;
+        if (provisioner.isEmpty()) return;
 
-        RestartActions restartActions = configChangeActions.getRestartActions().useForInternalRestart(internalRedeploy);
-        if (restartActions.isEmpty()) return;
+        Set<String> nodesToRestart = session.getActivationTriggers().nodeRestarts().stream().map(NodeRestart::hostname).collect(toSet());
+        if (nodesToRestart.isEmpty()) return;
 
-        Set<String> hostnames = restartActions.hostnames();
-        waitForConfigToConverge(applicationId, hostnames);
+        // TODO: replace this with a maintainer that waits for active config >= this session's config generation,
+        //       and let config convergence waiter in controller also check _pending_ restarts, maintained by that.
+        //       Here, we'll then instead hand these restarts over to that maintainer, with our session id.
+        waitForConfigToConverge(applicationId, nodesToRestart);
 
-        provisioner.get().restart(applicationId, HostFilter.from(hostnames));
-        deployLogger.log(Level.INFO, String.format("Scheduled service restart of %d nodes: %s",
-                                                   hostnames.size(), hostnames.stream().sorted().collect(Collectors.joining(", "))));
+        provisioner.get().restart(applicationId, HostFilter.from(nodesToRestart));
+        String restartsMessage = String.format("Scheduled service restart of %d nodes: %s",
+                                               nodesToRestart.size(), nodesToRestart.stream().sorted().collect(Collectors.joining(", ")));
+        deployLogger.log(Level.INFO, restartsMessage);
         log.info(String.format("%sScheduled service restart of %d nodes: %s",
-                               session.logPre(), hostnames.size(), restartActions.format()));
+                               session.logPre(), nodesToRestart.size(), restartsMessage));
         this.configChangeActions = configChangeActions.withRestartActions(new RestartActions());
     }
 
@@ -222,11 +225,10 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
                 .collect(Collectors.joining(", "));
     }
 
-    private void storeReindexing(ApplicationId applicationId, long requiredSession) {
+    private void storeReindexing(ApplicationId applicationId) {
         applicationRepository.modifyReindexing(applicationId, reindexing -> {
-            if (configChangeActions != null)
-                for (ReindexActions.Entry entry : configChangeActions.getReindexActions().getEntries())
-                    reindexing = reindexing.withPending(entry.getClusterName(), entry.getDocumentType(), requiredSession);
+            for (Reindexing entry : session.getActivationTriggers().reindexings())
+                reindexing = reindexing.withPending(entry.clusterId(), entry.documentType(), session.getSessionId());
 
             return reindexing;
         });
@@ -272,7 +274,7 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
      * @param force whether activation of this model should be forced
      */
     private static Supplier<PrepareParams> createPrepareParams(
-            Clock clock, Duration timeout, Session session,
+            Clock clock, Duration timeout, Session session, boolean isInternalRedeployment,
             boolean isBootstrap, boolean ignoreValidationErrors, boolean force, boolean waitForResourcesInPrepare) {
 
         // Use supplier because we shouldn't/can't create this before validateSessionStatus() for prepared deployments,
@@ -286,6 +288,7 @@ public class Deployment implements com.yahoo.config.provision.Deployment {
                     .timeoutBudget(timeoutBudget)
                     .ignoreValidationErrors(ignoreValidationErrors)
                     .isBootstrap(isBootstrap)
+                    .isInternalRedeployment(isInternalRedeployment)
                     .force(force)
                     .waitForResourcesInPrepare(waitForResourcesInPrepare)
                     .tenantSecretStores(session.getTenantSecretStores())
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/http/v2/response/SessionPrepareAndActivateResponse.java b/configserver/src/main/java/com/yahoo/vespa/config/server/http/v2/response/SessionPrepareAndActivateResponse.java
index a794b57aa89..1e6f7dfe45e 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/http/v2/response/SessionPrepareAndActivateResponse.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/http/v2/response/SessionPrepareAndActivateResponse.java
@@ -24,15 +24,17 @@ public class SessionPrepareAndActivateResponse extends SlimeJsonResponse {
         String message = "Session " + result.sessionId() + " for tenant '" + tenantName.value() + "' prepared and activated.";
         Cursor root = slime.get();
 
-        root.setString("tenant", tenantName.value());
         root.setString("session-id", Long.toString(result.sessionId()));
-        root.setString("url", "http://" + request.getHost() + ":" + request.getPort() +
-                "/application/v2/tenant/" + tenantName +
-                "/application/" + applicationId.application().value() +
-                "/environment/" + zone.environment().value() +
-                "/region/" + zone.region().value() +
-                "/instance/" + applicationId.instance().value());
         root.setString("message", message);
+
+        // TODO: remove unused fields, but add whether activation was successful.
+        root.setString("tenant", tenantName.value());
+        root.setString("url", "http://" + request.getHost() + ":" + request.getPort() +
+                              "/application/v2/tenant/" + tenantName +
+                              "/application/" + applicationId.application().value() +
+                              "/environment/" + zone.environment().value() +
+                              "/region/" + zone.region().value() +
+                              "/instance/" + applicationId.instance().value());
         new ConfigChangeActionsSlimeConverter(result.configChangeActions()).toSlime(root);
     }
 
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggers.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggers.java
new file mode 100644
index 00000000000..191f936c333
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggers.java
@@ -0,0 +1,37 @@
+package com.yahoo.vespa.config.server.session;
+
+import com.yahoo.vespa.config.server.configchange.ConfigChangeActions;
+
+import java.util.List;
+
+/**
+ * Events that should trigger upon activation of a session.
+ * A prepared session is always prepared with a specific origin session, unless it is the first session in a zone,
+ * and activation of a session fails if the current session changes before the prepared session is activated.
+ * Therefore, the trigger events computed upon preparation of a session will always be valid when a session is activated,
+ * and can be stored as part of the session state.
+ * This is needed to properly handle activation of sessions on different servers than the preparing ones.
+ *
+ * @author jonmv
+ */
+public record ActivationTriggers(List<NodeRestart> nodeRestarts, List<Reindexing> reindexings) {
+
+    private static final ActivationTriggers empty = new ActivationTriggers(List.of(), List.of());
+
+    public record NodeRestart(String hostname) { }
+    public record Reindexing(String clusterId, String documentType) { }
+
+    public static ActivationTriggers empty() { return empty; }
+
+    public static ActivationTriggers from(ConfigChangeActions configChangeActions, boolean isInternalRedeployment) {
+        return new ActivationTriggers(configChangeActions.getRestartActions()
+                                                         .useForInternalRestart(isInternalRedeployment)
+                                                         .hostnames().stream()
+                                                         .map(NodeRestart::new)
+                                                         .toList(),
+                                      configChangeActions.getReindexActions().getEntries().stream()
+                                                         .map(entry -> new Reindexing(entry.getClusterName(), entry.getDocumentType()))
+                                                         .toList());
+    }
+
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializer.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializer.java
new file mode 100644
index 00000000000..5f67de0ccca
--- /dev/null
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializer.java
@@ -0,0 +1,60 @@
+package com.yahoo.vespa.config.server.session;
+
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.slime.SlimeUtils;
+import com.yahoo.vespa.config.server.session.ActivationTriggers.NodeRestart;
+import com.yahoo.vespa.config.server.session.ActivationTriggers.Reindexing;
+
+import java.util.List;
+
+import static com.yahoo.yolean.Exceptions.uncheck;
+
+/**
+ * @author jonmv
+ */
+public class ActivationTriggersSerializer {
+
+    static final String NODE_RESTARTS = "nodeRestarts";
+    static final String REINDEXINGS = "reindexings";
+    static final String CLUSTER_NAME = "clusterName";
+    static final String DOCUMENT_TYPE = "documentType";
+
+    public static byte[] toJson(ActivationTriggers triggers) {
+        Slime root = new Slime();
+        toSlime(triggers, root.setObject());
+        return uncheck(() -> SlimeUtils.toJsonBytes(root));
+    }
+
+    public static ActivationTriggers fromJson(byte[] json) {
+        return fromSlime(SlimeUtils.jsonToSlime(json).get());
+    }
+
+    public static void toSlime(ActivationTriggers triggers, Cursor object) {
+        Cursor nodeRestarts = object.setArray(NODE_RESTARTS);
+        for (NodeRestart nodeRestart : triggers.nodeRestarts())
+            nodeRestarts.addString(nodeRestart.hostname());
+
+        Cursor reindexings = object.setArray(REINDEXINGS);
+        for (Reindexing reindexing : triggers.reindexings()) {
+            Cursor entry = reindexings.addObject();
+            entry.setString(CLUSTER_NAME, reindexing.clusterId());
+            entry.setString(DOCUMENT_TYPE, reindexing.documentType());
+        }
+    }
+
+    public static ActivationTriggers fromSlime(Cursor object) {
+        if ( ! object.valid())
+            return ActivationTriggers.empty();
+
+        List<NodeRestart> nodeRestarts = SlimeUtils.entriesStream(object.field(NODE_RESTARTS))
+                                                   .map(entry -> new NodeRestart(entry.asString()))
+                                                   .toList();
+        List<Reindexing> reindexings = SlimeUtils.entriesStream(object.field(REINDEXINGS))
+                                                   .map(entry -> new Reindexing(entry.field(CLUSTER_NAME).asString(),
+                                                                                entry.field(DOCUMENT_TYPE).asString()))
+                                                   .toList();
+        return new ActivationTriggers(nodeRestarts, reindexings);
+    }
+
+}
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/PrepareParams.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/PrepareParams.java
index 19f227f8dc8..ec24cc17284 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/PrepareParams.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/PrepareParams.java
@@ -65,6 +65,7 @@ public final class PrepareParams {
     private final boolean dryRun;
     private final boolean verbose;
     private final boolean isBootstrap;
+    private final boolean isInternalRedeployment;
     private final boolean force;
     private final boolean waitForResourcesInPrepare;
     private final Optional<Version> vespaVersion;
@@ -84,6 +85,7 @@ public final class PrepareParams {
                           boolean dryRun,
                           boolean verbose,
                           boolean isBootstrap,
+                          boolean isInternalRedeployment,
                           Optional<Version> vespaVersion,
                           List<ContainerEndpoint> containerEndpoints,
                           Optional<EndpointCertificateMetadata> endpointCertificateMetadata,
@@ -102,6 +104,7 @@ public final class PrepareParams {
         this.dryRun = dryRun;
         this.verbose = verbose;
         this.isBootstrap = isBootstrap;
+        this.isInternalRedeployment = isInternalRedeployment;
         this.vespaVersion = vespaVersion;
         this.containerEndpoints = containerEndpoints;
         this.endpointCertificateMetadata = endpointCertificateMetadata;
@@ -124,6 +127,7 @@ public final class PrepareParams {
         private boolean isBootstrap = false;
         private boolean force = false;
         private boolean waitForResourcesInPrepare = false;
+        private boolean isInternalRedeployment = false;
         private ApplicationId applicationId = null;
         private TimeoutBudget timeoutBudget = new TimeoutBudget(Clock.systemUTC(), Duration.ofSeconds(60));
         private Optional<Version> vespaVersion = Optional.empty();
@@ -164,6 +168,11 @@ public final class PrepareParams {
             return this;
         }
 
+        public Builder isInternalRedeployment(boolean isInternalRedeployment) {
+            this.isInternalRedeployment = isInternalRedeployment;
+            return this;
+        }
+
         public Builder timeoutBudget(TimeoutBudget timeoutBudget) {
             this.timeoutBudget = timeoutBudget;
             return this;
@@ -285,6 +294,7 @@ public final class PrepareParams {
                                      dryRun,
                                      verbose,
                                      isBootstrap,
+                                     isInternalRedeployment,
                                      vespaVersion,
                                      containerEndpoints,
                                      endpointCertificateMetadata,
@@ -424,6 +434,8 @@ public final class PrepareParams {
 
     public boolean isBootstrap() { return isBootstrap; }
 
+    public boolean isInternalRedeployment() { return isInternalRedeployment; }
+
     public boolean force() { return force; }
 
     public boolean waitForResourcesInPrepare() { return waitForResourcesInPrepare; }
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/Session.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/Session.java
index 37ebfa12e7e..39025aa8374 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/Session.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/Session.java
@@ -158,6 +158,10 @@ public abstract class Session implements Comparable<Session>  {
         return sessionZooKeeperClient.readDataplaneTokens();
     }
 
+    public ActivationTriggers getActivationTriggers() {
+        return sessionZooKeeperClient.readActivationTriggers();
+    }
+
     public SessionZooKeeperClient getSessionZooKeeperClient() { return sessionZooKeeperClient; }
 
     private Transaction createSetStatusTransaction(Status status) {
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionData.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionData.java
index 6c27eefc055..1757998882e 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionData.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionData.java
@@ -41,7 +41,8 @@ public record SessionData(ApplicationId applicationId,
                           List<TenantSecretStore> tenantSecretStores,
                           List<X509Certificate> operatorCertificates,
                           Optional<CloudAccount> cloudAccount,
-                          List<DataplaneToken> dataplaneTokens) {
+                          List<DataplaneToken> dataplaneTokens,
+                          ActivationTriggers activationTriggers) {
 
     // NOTE: Any state added here MUST also be propagated in com.yahoo.vespa.config.server.deploy.Deployment.prepare()
     static final String APPLICATION_ID_PATH = "applicationId";
@@ -56,6 +57,7 @@ public record SessionData(ApplicationId applicationId,
     static final String CLOUD_ACCOUNT_PATH = "cloudAccount";
     static final String DATAPLANE_TOKENS_PATH = "dataplaneTokens";
     static final String SESSION_DATA_PATH = "sessionData";
+    static final String ACTIVATION_TRIGGERS_PATH = "activationTriggers";
 
     public byte[] toJson() {
         try {
@@ -87,6 +89,8 @@ public record SessionData(ApplicationId applicationId,
 
         Cursor dataplaneTokensArray = object.setArray(DATAPLANE_TOKENS_PATH);
         DataplaneTokenSerializer.toSlime(dataplaneTokens, dataplaneTokensArray);
+
+        ActivationTriggersSerializer.toSlime(activationTriggers, object.setObject(ACTIVATION_TRIGGERS_PATH));
     }
 
     static SessionData fromSlime(Slime slime) {
@@ -103,7 +107,8 @@ public record SessionData(ApplicationId applicationId,
                                TenantSecretStoreSerializer.listFromSlime(cursor.field(TENANT_SECRET_STORES_PATH)),
                                OperatorCertificateSerializer.fromSlime(cursor.field(OPERATOR_CERTIFICATES_PATH)),
                                optionalString(cursor.field(CLOUD_ACCOUNT_PATH)).map(CloudAccount::from),
-                               DataplaneTokenSerializer.fromSlime(cursor.field(DATAPLANE_TOKENS_PATH)));
+                               DataplaneTokenSerializer.fromSlime(cursor.field(DATAPLANE_TOKENS_PATH)),
+                               ActivationTriggersSerializer.fromSlime(cursor.field(ACTIVATION_TRIGGERS_PATH)));
     }
 
 }
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionPreparer.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionPreparer.java
index 5c049c61c1a..87d3c8ce093 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionPreparer.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionPreparer.java
@@ -358,7 +358,8 @@ public class SessionPreparer {
                                   params.tenantSecretStores(),
                                   params.operatorCertificates(),
                                   params.cloudAccount(),
-                                  params.dataplaneTokens());
+                                  params.dataplaneTokens(),
+                                  ActivationTriggers.from(prepareResult.getConfigChangeActions(), params.isInternalRedeployment()));
             checkTimeout("write state to zookeeper");
         }
 
@@ -401,7 +402,8 @@ public class SessionPreparer {
                                        List<TenantSecretStore> tenantSecretStores,
                                        List<X509Certificate> operatorCertificates,
                                        Optional<CloudAccount> cloudAccount,
-                                       List<DataplaneToken> dataplaneTokens) {
+                                       List<DataplaneToken> dataplaneTokens,
+                                       ActivationTriggers activationTriggers) {
         var zooKeeperDeplyer = new ZooKeeperDeployer(curator, deployLogger, applicationId, zooKeeperClient.sessionId());
         try {
             zooKeeperDeplyer.deploy(applicationPackage, fileRegistryMap, allocatedHosts);
@@ -417,6 +419,7 @@ public class SessionPreparer {
                                           operatorCertificates,
                                           cloudAccount,
                                           dataplaneTokens,
+                                          activationTriggers,
                                           writeSessionData);
         } catch (RuntimeException | IOException e) {
             zooKeeperDeplyer.cleanup();
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionRepository.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionRepository.java
index 47b8215b52d..8da58de26b8 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionRepository.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionRepository.java
@@ -606,6 +606,7 @@ public class SessionRepository {
                                 existingSession.getOperatorCertificates(),
                                 existingSession.getCloudAccount(),
                                 existingSession.getDataplaneTokens(),
+                                existingSession.getActivationTriggers(),
                                 writeSessionData);
     }
 
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionSerializer.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionSerializer.java
index f71476c5770..438db91721f 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionSerializer.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionSerializer.java
@@ -33,7 +33,7 @@ public class SessionSerializer {
                Instant created, Optional<FileReference> fileReference, Optional<DockerImage> dockerImageRepository,
                Version vespaVersion, Optional<AthenzDomain> athenzDomain, Optional<Quota> quota,
                List<TenantSecretStore> tenantSecretStores, List<X509Certificate> operatorCertificates,
-               Optional<CloudAccount> cloudAccount, List<DataplaneToken> dataplaneTokens,
+               Optional<CloudAccount> cloudAccount, List<DataplaneToken> dataplaneTokens, ActivationTriggers activationTriggers,
                BooleanFlag writeSessionData) {
         zooKeeperClient.writeApplicationId(applicationId);
         zooKeeperClient.writeApplicationPackageReference(fileReference);
@@ -45,6 +45,7 @@ public class SessionSerializer {
         zooKeeperClient.writeOperatorCertificates(operatorCertificates);
         zooKeeperClient.writeCloudAccount(cloudAccount);
         zooKeeperClient.writeDataplaneTokens(dataplaneTokens);
+        zooKeeperClient.writeActivationTriggers(activationTriggers);
         if (writeSessionData.value())
             zooKeeperClient.writeSessionData(new SessionData(applicationId,
                                                              fileReference,
@@ -56,7 +57,8 @@ public class SessionSerializer {
                                                              tenantSecretStores,
                                                              operatorCertificates,
                                                              cloudAccount,
-                                                             dataplaneTokens));
+                                                             dataplaneTokens,
+                                                             activationTriggers));
     }
 
     SessionData read(SessionZooKeeperClient zooKeeperClient, BooleanFlag readSessionData) {
@@ -82,7 +84,8 @@ public class SessionSerializer {
                                zooKeeperClient.readTenantSecretStores(),
                                zooKeeperClient.readOperatorCertificates(),
                                zooKeeperClient.readCloudAccount(),
-                               zooKeeperClient.readDataplaneTokens());
+                               zooKeeperClient.readDataplaneTokens(),
+                               zooKeeperClient.readActivationTriggers());
     }
 
 }
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
index cbd6e956d1d..bcffecf28ea 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClient.java
@@ -42,6 +42,7 @@ import java.util.List;
 import java.util.Optional;
 import java.util.logging.Level;
 
+import static com.yahoo.vespa.config.server.session.SessionData.ACTIVATION_TRIGGERS_PATH;
 import static com.yahoo.vespa.config.server.session.SessionData.APPLICATION_ID_PATH;
 import static com.yahoo.vespa.config.server.session.SessionData.APPLICATION_PACKAGE_REFERENCE_PATH;
 import static com.yahoo.vespa.config.server.session.SessionData.ATHENZ_DOMAIN;
@@ -353,6 +354,16 @@ public class SessionZooKeeperClient {
                 .orElse(List.of());
     }
 
+    public void writeActivationTriggers(ActivationTriggers activationTriggers) {
+        curator.set(sessionPath.append(ACTIVATION_TRIGGERS_PATH), ActivationTriggersSerializer.toJson(activationTriggers));
+    }
+
+    public ActivationTriggers readActivationTriggers() {
+        return curator.getData(sessionPath.append(ACTIVATION_TRIGGERS_PATH))
+                      .map(ActivationTriggersSerializer::fromJson)
+                      .orElse(ActivationTriggers.empty());
+    }
+
     /**
      * Create necessary paths atomically for a new session.
      *
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializerTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializerTest.java
new file mode 100644
index 00000000000..97f079d9ee3
--- /dev/null
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/session/ActivationTriggersSerializerTest.java
@@ -0,0 +1,27 @@
+package com.yahoo.vespa.config.server.session;
+
+import com.yahoo.vespa.config.server.session.ActivationTriggers.NodeRestart;
+import com.yahoo.vespa.config.server.session.ActivationTriggers.Reindexing;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+/**
+ * @author jonmv
+ */
+class ActivationTriggersSerializerTest {
+
+    @Test
+    void testSerialization() {
+        ActivationTriggers triggers = new ActivationTriggers(List.of(new NodeRestart("node1"),
+                                                                     new NodeRestart("node2")),
+                                                             List.of(new Reindexing("cluster1", "type1"),
+                                                                     new Reindexing("cluster1", "type2"),
+                                                                     new Reindexing("cluster2", "type1")));
+        assertEquals(triggers, ActivationTriggersSerializer.fromJson(ActivationTriggersSerializer.toJson(triggers)));
+    }
+
+}
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClientTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClientTest.java
index 7fcaae05224..a7892bd4c56 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClientTest.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/session/SessionZooKeeperClientTest.java
@@ -14,9 +14,7 @@ import com.yahoo.vespa.config.server.tenant.TenantRepository;
 import com.yahoo.vespa.curator.Curator;
 import com.yahoo.vespa.curator.mock.MockCurator;
 import org.junit.Before;
-import org.junit.Rule;
 import org.junit.Test;
-import org.junit.rules.ExpectedException;
 
 import java.time.Instant;
 import java.util.List;
@@ -27,6 +25,7 @@ import static com.yahoo.vespa.config.server.session.SessionData.SESSION_DATA_PAT
 import static com.yahoo.vespa.config.server.zookeeper.ZKApplication.SESSIONSTATE_ZK_SUBPATH;
 import static java.math.BigDecimal.valueOf;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -38,10 +37,6 @@ public class SessionZooKeeperClientTest {
 
     private Curator curator;
 
-    @SuppressWarnings("deprecation")
-    @Rule
-    public ExpectedException expectedException = ExpectedException.none();
-
     @Before
     public void setup() {
         curator = new MockCurator();
@@ -107,9 +102,9 @@ public class SessionZooKeeperClientTest {
         int sessionId = 3;
         SessionZooKeeperClient zkc = createSessionZKClient(sessionId);
 
-        expectedException.expect(IllegalArgumentException.class);
-        expectedException.expectMessage("Cannot write application id 'someOtherTenant.foo.bim' for tenant 'default'");
-        zkc.writeApplicationId(id);
+        assertEquals("Cannot write application id 'someOtherTenant.foo.bim' for tenant 'default'",
+                     assertThrows(IllegalArgumentException.class,
+                                  () -> zkc.writeApplicationId(id)).getMessage());
     }
 
     @Test
@@ -176,12 +171,13 @@ public class SessionZooKeeperClientTest {
                                              List.of(),
                                              List.of(),
                                              Optional.empty(),
-                                             List.of()));
+                                             List.of(),
+                                             ActivationTriggers.empty()));
         Path path = sessionPath(sessionId).append(SESSION_DATA_PATH);
         assertTrue(curator.exists(path));
         String data = Utf8.toString(curator.getData(path).get());
         assertTrue(data.contains("{\"applicationId\":\"default:default:default\",\"applicationPackageReference\":\"foo\",\"version\":\"8.195.1\",\"createTime\":"));
-        assertTrue(data.contains(",\"tenantSecretStores\":[],\"operatorCertificates\":[],\"dataplaneTokens\":[]}"));
+        assertTrue(data.contains(",\"tenantSecretStores\":[],\"operatorCertificates\":[],\"dataplaneTokens\":[],\"activationTriggers\":{\"nodeRestarts\":[],\"reindexings\":[]}"));
     }
 
     private void assertApplicationIdParse(long sessionId, String idString, String expectedIdString) {