diff --git a/Documentation/config-gerrit.txt b/Documentation/config-gerrit.txt
index 3e778dc777..f4a9588fbd 100644
--- a/Documentation/config-gerrit.txt
+++ b/Documentation/config-gerrit.txt
@@ -2777,6 +2777,16 @@ reindex] must be performed.
 This section is only used if Gerrit runs in slave mode, otherwise it is
 ignored.
 
+[[index.scheduledIndexer.runOnStartup]]index.scheduledIndexer.runOnStartup::
++
+Whether the scheduled indexer should run once immediately on startup.
+If set to `true` the slave startup is blocked until all stale groups
+were reindexed. Enabling this allows to prevent that slaves that were
+offline for a longer period of time run with outdated group information
+until the first scheduled indexing is done.
++
+Defaults to `true`.
+
 [[index.scheduledIndexer.enabled]]index.scheduledIndexer.enabled::
 +
 Whether the scheduled indexer is enabled. If the scheduled indexer is
diff --git a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
index 93235634b5..77dc8ea5e1 100644
--- a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
@@ -343,9 +343,6 @@ public abstract class AbstractDaemonTest {
       server.getTestInjector().injectMembers(resetter);
     }
     initSsh();
-    // The server restart threw away all indices. Only reindex all groups as we only have the group
-    // index in slave mode.
-    reindexAllGroups();
   }
 
   private void reindexAllGroups() throws OrmException, IOException, ConfigInvalidException {
diff --git a/java/com/google/gerrit/server/group/PeriodicGroupIndexer.java b/java/com/google/gerrit/server/group/PeriodicGroupIndexer.java
index 2fcc5e0aba..e99440b56c 100644
--- a/java/com/google/gerrit/server/group/PeriodicGroupIndexer.java
+++ b/java/com/google/gerrit/server/group/PeriodicGroupIndexer.java
@@ -82,6 +82,11 @@ public class PeriodicGroupIndexer implements Runnable {
 
     @Override
     public void start() {
+      boolean runOnStartup = cfg.getBoolean("index", "scheduledIndexer", "runOnStartup", true);
+      if (runOnStartup) {
+        runner.run();
+      }
+
       boolean isEnabled = cfg.getBoolean("index", "scheduledIndexer", "enabled", true);
       if (!isEnabled) {
         log.warn("index.scheduledIndexer is disabled");
diff --git a/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java b/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
index 5e10e37e04..2d5703d251 100644
--- a/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
@@ -1262,14 +1262,15 @@ public class GroupsIT extends AbstractDaemonTest {
         groups.getAllGroupReferences(db).map(GroupReference::getUUID).collect(toList());
     assertThat(expectedGroups.size()).isAtLeast(2);
 
+    // Restart the server as slave, on startup of the slave all groups are indexed.
     restartAsSlave();
 
     GroupIndexedCounter groupIndexedCounter = new GroupIndexedCounter();
     RegistrationHandle groupIndexEventCounterHandle =
         groupIndexedListeners.add(groupIndexedCounter);
     try {
-      // On startup of the slave the test framework ensures that the group index is up-to-date.
-      // Hence running the reindexer doesn't need to reindex any group.
+      // Running the reindexer right after startup should not need to reindex any group since
+      // reindexing was already done on startup.
       slaveGroupIndexer.run();
       groupIndexedCounter.assertNoReindex();
 
@@ -1308,6 +1309,33 @@ public class GroupsIT extends AbstractDaemonTest {
     }
   }
 
+  @Test
+  @Sandboxed
+  @GerritConfig(name = "index.scheduledIndexer.runOnStartup", value = "false")
+  @GerritConfig(name = "index.scheduledIndexer.enabled", value = "false")
+  @GerritConfig(name = "index.autoReindexIfStale", value = "false")
+  @IgnoreGroupInconsistencies
+  public void disabledReindexGroupsOnStartupSlaveMode() throws Exception {
+    assume().that(readGroupsFromNoteDb()).isTrue();
+
+    List<AccountGroup.UUID> expectedGroups =
+        groups.getAllGroupReferences(db).map(GroupReference::getUUID).collect(toList());
+    assertThat(expectedGroups.size()).isAtLeast(2);
+
+    restartAsSlave();
+
+    GroupIndexedCounter groupIndexedCounter = new GroupIndexedCounter();
+    RegistrationHandle groupIndexEventCounterHandle =
+        groupIndexedListeners.add(groupIndexedCounter);
+    try {
+      // No group indexing happened on startup. All groups should be reindexed now.
+      slaveGroupIndexer.run();
+      groupIndexedCounter.assertReindexOf(expectedGroups);
+    } finally {
+      groupIndexEventCounterHandle.remove();
+    }
+  }
+
   private void assertStaleGroupAndReindex(AccountGroup.UUID groupUuid) throws IOException {
     // Evict group from cache to be sure that we use the index state for staleness checks.
     groupCache.evict(groupUuid);