# WebSocket Jenkins agent disconnects (java.util.concurrent.TimeoutException: Ping started at 1775776035301 hasn't completed by 1775776275302)

**URL:** <https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794>\
**Category:** Ask a question\
**Created:** [April 10, 2026, 4:46am UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794 "2026-04-10T04:46:26Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![nithishgwd](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nithishgwd/32/20826_2.png) [@nithishgwd](https://community.jenkins.io/u/nithishgwd)\
**Post date:** [April 10, 2026, 4:46am UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794/1 "2026-04-10T04:46:26Z")

</div>

Hi,

We are seeing random disconnects on our Jenkins inbound agents using WebSocket.

Jenkins version: **2.541.3**  
Remoting version: **3352.v17a\_fb\_4b\_2773f**  
Agent Java: **OpenJDK 21.0.10**  
Controller Java: **OpenJDK 21.0.9 Temurin**

Our setup is:

`agent → AWS Global Accelerator → ALB → Jenkins controller`

What we are seeing:

- Agents disconnect randomly, sometimes even while a job is running

- On the agent side we see:

- Immediately after that, the agent reconnects and comes back online

- On the controller side we mostly only see:

What we checked so far:

- Agent machine looks healthy

- ALB logs do not show clear errors like 460/504 around the disconnect window

- Connection is over WebSocket on HTTPS (443)

So it does not look like a normal node crash. It feels like the connection stops responding for some time and Jenkins later closes it due to ping timeout.

Questions:

1. Has anyone seen WebSocket agents disconnect like this without clear errors?

2. Could this be related to Jenkins remoting or WebSocket handling?

3. Are there recommended settings for ping interval / timeout or WebSocket keepalive?

Thanks!

---

<div class="post-metadata">

**Author:** ![deekshith-silabs](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/deekshith-silabs/32/21325_2.png) [@deekshith-silabs](https://community.jenkins.io/u/deekshith-silabs)\
**Post date:** [May 12, 2026, 7:08am UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794/2 "2026-05-12T07:08:15Z")

</div>

We’re seeing the **same problem in Jenkins** with the **same version** , and it’s making builds **unstable**. Any suggestions would be appreciated.

---

<div class="post-metadata">

**Author:** ![nithishgwd](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nithishgwd/32/20826_2.png) [@nithishgwd](https://community.jenkins.io/u/nithishgwd)\
**Post date:** [May 12, 2026, 1:29pm UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794/3 "2026-05-12T13:29:43Z")

</div>

We tried AWS GA as well, but nothing worked and we experienced different types of errors. Since the issue is still related to disconnection, we are moving to use an AWS ALB for the Jenkins URL and an AWS NLB for the node connection.

REF: [Inbound WebSocket Jenkins agent intermittently disconnects with Connection timed out / Read side closed · Issue #26726 · jenkinsci/jenkins · GitHub](https://github.com/jenkinsci/jenkins/issues/26726#issuecomment-4363227481)

---

<div class="post-metadata">

**Author:** ![nithishgwd](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nithishgwd/32/20826_2.png) [@nithishgwd](https://community.jenkins.io/u/nithishgwd)\
**Post date:** [May 12, 2026, 1:30pm UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794/4 "2026-05-12T13:30:48Z")

</div>

will reply you back in week, about stability using NLB

---

<div class="post-metadata">

**Author:** ![nithishgwd](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nithishgwd/32/20826_2.png) [@nithishgwd](https://community.jenkins.io/u/nithishgwd)\
**Post date:** [May 18, 2026, 2:00am UTC](https://community.jenkins.io/t/websocket-jenkins-agent-disconnects-java-util-concurrent-timeoutexception-ping-started-at-1775776035301-hasnt-completed-by-1775776275302/36794/5 "2026-05-18T02:00:30Z")

</div>

We observed improved stability after moving the node connections to the AWS NLB.