Nomad version

Nomad v2.0.3
BuildDate 2026-06-09T17:33:24Z
Revision a2a5fee

Operating system and Environment details

cat /etc/os-release | head -2 ; uname -r
PRETTY_NAME="Ubuntu 22.04.5 LTS"
NAME="Ubuntu"
5.15.0-179-generic

Issue

In UI when I want enter into container get this error immediately:

Select a task to start your session.
Customize your command, then hit ‘return’ to run.
$ nomad alloc exec -i -t -task utils-task 774dd5cf bash

The connection has closed.

In browser network console I see with error 500 and NS_ERROR_WEBSOCKET_CONNECTION_REFUSED (with IP the same). :

GET wss://nomad-master.service.consul:4646/v1/client/allocation/774dd5cf-6233-a74e-c34c-323ef24cc966/exec?task=utils-task&tty=true&ws_handshake=true&command=["bash"]

Nomad Server logs:

journalctl -u nomad.service -f

Jul 07 11:09:48 nomad-server1 nomad[1693057]: 2026-07-07T11:09:48.883Z [ERROR] http: request failed: method=GET path="/v1/client/allocation/774dd5cf-6233-a74e-c34c-323ef24cc966/exec?task=utils-task&tty=true&ws_handshake=true&region=global&command=%5B%22%2Fbin%2Fbash%22%5D" error="websocket connection not found in context" code=500

Reproduction steps

Click any job -> task name ->exec -> then enter on welcome screen

Expected Result

I can enter to the container

Actual Result

Get error The connection has closed in my 3 Nomad environments.

In 2.0.1 working fine.
Thanks!