diff --git a/x-pack/legacy/plugins/cross_cluster_replication/public/np_ready/app/services/api.js b/x-pack/legacy/plugins/cross_cluster_replication/public/np_ready/app/services/api.js
index b50c36aa8df9f..24bc7e17356e2 100644
--- a/x-pack/legacy/plugins/cross_cluster_replication/public/np_ready/app/services/api.js
+++ b/x-pack/legacy/plugins/cross_cluster_replication/public/np_ready/app/services/api.js
@@ -145,9 +145,35 @@ export const updateFollowerIndex = (id, followerIndex) => {
   if (isUsingAdvancedSettings) {
     uiMetrics.push(UIM_FOLLOWER_INDEX_USE_ADVANCED_OPTIONS);
   }
+
+  const {
+    maxReadRequestOperationCount,
+    maxOutstandingReadRequests,
+    maxReadRequestSize,
+    maxWriteRequestOperationCount,
+    maxWriteRequestSize,
+    maxOutstandingWriteRequests,
+    maxWriteBufferCount,
+    maxWriteBufferSize,
+    maxRetryDelay,
+    readPollTimeout,
+  } = followerIndex;
+
   const request = httpClient.put(`${API_BASE_PATH}/follower_indices/${encodeURIComponent(id)}`, {
-    body: JSON.stringify(followerIndex),
+    body: JSON.stringify({
+      maxReadRequestOperationCount,
+      maxOutstandingReadRequests,
+      maxReadRequestSize,
+      maxWriteRequestOperationCount,
+      maxWriteRequestSize,
+      maxOutstandingWriteRequests,
+      maxWriteBufferCount,
+      maxWriteBufferSize,
+      maxRetryDelay,
+      readPollTimeout,
+    }),
   });
+
   return trackUserRequest(request, uiMetrics);
 };
 
diff --git a/x-pack/legacy/plugins/cross_cluster_replication/server/np_ready/routes/api/follower_index.ts b/x-pack/legacy/plugins/cross_cluster_replication/server/np_ready/routes/api/follower_index.ts
index 3896e1c02c915..1d7dacf4a8688 100644
--- a/x-pack/legacy/plugins/cross_cluster_replication/server/np_ready/routes/api/follower_index.ts
+++ b/x-pack/legacy/plugins/cross_cluster_replication/server/np_ready/routes/api/follower_index.ts
@@ -164,6 +164,18 @@ export const registerFollowerIndexRoutes = ({ router, __LEGACY }: RouteDependenc
       path: `${API_BASE_PATH}/follower_indices/{id}`,
       validate: {
         params: schema.object({ id: schema.string() }),
+        body: schema.object({
+          maxReadRequestOperationCount: schema.maybe(schema.number()),
+          maxOutstandingReadRequests: schema.maybe(schema.number()),
+          maxReadRequestSize: schema.maybe(schema.string()), // byte value
+          maxWriteRequestOperationCount: schema.maybe(schema.number()),
+          maxWriteRequestSize: schema.maybe(schema.string()), // byte value
+          maxOutstandingWriteRequests: schema.maybe(schema.number()),
+          maxWriteBufferCount: schema.maybe(schema.number()),
+          maxWriteBufferSize: schema.maybe(schema.string()), // byte value
+          maxRetryDelay: schema.maybe(schema.string()), // time value
+          readPollTimeout: schema.maybe(schema.string()), // time value
+        }),
       },
     },
     licensePreRoutingFactory({
diff --git a/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.helpers.js b/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.helpers.js
index dbcb6bf819749..294db29f6dce4 100644
--- a/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.helpers.js
+++ b/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.helpers.js
@@ -13,7 +13,45 @@ export const registerHelpers = supertest => {
 
   const loadFollowerIndices = () => supertest.get(`${API_BASE_PATH}/follower_indices`);
 
-  const getFollowerIndex = name => supertest.get(`${API_BASE_PATH}/follower_indices/${name}`);
+  const getFollowerIndex = (name, waitUntilIsActive = false) => {
+    const maxRetries = 10;
+    const delayBetweenRetries = 500;
+    let retryCount = 0;
+
+    const proceed = async () => {
+      const response = await supertest.get(`${API_BASE_PATH}/follower_indices/${name}`);
+
+      if (waitUntilIsActive && response.body.status !== 'active') {
+        retryCount += 1;
+
+        if (retryCount > maxRetries) {
+          throw new Error('Error waiting for follower index to be active.');
+        }
+
+        return new Promise(resolve => setTimeout(resolve, delayBetweenRetries)).then(proceed);
+      }
+
+      return response;
+    };
+
+    return {
+      expect: status =>
+        new Promise((resolve, reject) =>
+          proceed()
+            .then(response => {
+              if (status !== response.status) {
+                reject(new Error(`Expected status ${status} but got ${response.status}`));
+              }
+              return resolve(response);
+            })
+            .catch(reject)
+        ),
+      then: (resolve, reject) =>
+        proceed()
+          .then(resolve)
+          .catch(reject),
+    };
+  };
 
   const createFollowerIndex = (name = getRandomString(), payload = getFollowerIndexPayload()) => {
     followerIndicesCreated.push(name);
@@ -24,6 +62,13 @@ export const registerHelpers = supertest => {
       .send({ ...payload, name });
   };
 
+  const updateFollowerIndex = (name, payload) => {
+    return supertest
+      .put(`${API_BASE_PATH}/follower_indices/${name}`)
+      .set('kbn-xsrf', 'xxx')
+      .send(payload);
+  };
+
   const unfollowLeaderIndex = followerIndex => {
     const followerIndices = Array.isArray(followerIndex) ? followerIndex : [followerIndex];
     const followerIndicesToEncodedString = followerIndices
@@ -51,6 +96,7 @@ export const registerHelpers = supertest => {
     loadFollowerIndices,
     getFollowerIndex,
     createFollowerIndex,
+    updateFollowerIndex,
     unfollowAll,
   };
 };
diff --git a/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.js b/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.js
index 5f9ebbd2a0a3f..eabf474120f2b 100644
--- a/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.js
+++ b/x-pack/test/api_integration/apis/management/cross_cluster_replication/follower_indices.js
@@ -21,6 +21,7 @@ export default function({ getService }) {
     loadFollowerIndices,
     getFollowerIndex,
     createFollowerIndex,
+    updateFollowerIndex,
     unfollowAll,
   } = registerFollowerIndicesnHelpers(supertest);
 
@@ -92,6 +93,31 @@ export default function({ getService }) {
       });
     });
 
+    describe('update()', () => {
+      it('should update a follower index advanced settings', async () => {
+        // Create a follower index
+        const leaderIndex = await createIndex();
+        const followerIndex = getRandomString();
+        const initialValue = 1234;
+        const payload = getFollowerIndexPayload(leaderIndex, undefined, {
+          maxReadRequestOperationCount: initialValue,
+        });
+        await createFollowerIndex(followerIndex, payload);
+
+        // Verify that its advanced settings are correctly set
+        const { body } = await getFollowerIndex(followerIndex, true);
+        expect(body.maxReadRequestOperationCount).to.be(initialValue);
+
+        // Update the follower index
+        const updatedValue = 7777;
+        await updateFollowerIndex(followerIndex, { maxReadRequestOperationCount: updatedValue });
+
+        // Verify that the advanced settings are updated
+        const { body: updatedBody } = await getFollowerIndex(followerIndex, true);
+        expect(updatedBody.maxReadRequestOperationCount).to.be(updatedValue);
+      });
+    });
+
     describe('Advanced settings', () => {
       it('hard-coded values should match Elasticsearch default values', async () => {
         /**