(Yes, I did search first) After recently using the admin upgrade interface, my discourse instance stopped working, responding with 502 Bad Gateway. I’ve entered the container and it appears to be running an nginx that is expecting a server at localhost:3000, which is not running. (54) Waiting for new unicorn workers under 3802725 to start up... (54) Waiting for new unicorn workers under 3802725 to start up... (54) Old pid is: 3800363 New pid is: 3802725 config/unicorn_launcher: line 71: kill: (3802725) - No such process config/unicorn_launcher: line 15: kill: (3802725) - No such process (54) exiting ok: run: redis: (pid 62) 3418739s ok: run: postgres: (pid 53) 3418739s supervisor pid: 3803896 unicorn pid: 3803900 config/unicorn_launcher: line 71: kill: (3803900) - No such process config/unicorn_launcher: line 15: kill: (3803900) - No such process (3803896) exiting this is followed repeatedly by: ok: run: redis: (pid 64) 4905s ok: run: postgres: (pid 65) 4905s supervisor pid: 18571 unicorn pid: 18575 config/unicorn_launcher: line 71: kill: (18575) - No such process config/unicorn_launcher: line 15: kill: (18575) - No such process (18571) exiting I’d like to start this thread for help in debugging this; what’s the next step here - which command is Discourse trying to run. (I know I could find this out by reading/reverse engineering the code, but it may be useful to have a thread on this on the forum.) I’d be grateful for any pointers.

Start with search :wink: This looks similar? [image] 502 Bad Gateway after upgrade to 2.7.0beta2 Self-hosting Updated from cli: cd /var/discourse git pull ./launcher rebuild app Everything went ok but I got 502 Bad Gateway error. docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 6598e9407e29 local_discourse/app "/sbin/boot" 35 minutes ago Up 22 minutes 0.0.0.0:2045->80/tcp app ./launcher logs app (105) exiting ok: run: redis: (pid 47) 17s ok: run: postgres: (pid 44) 17s supervisor pid: 114 unicorn pid: 118 confi… Are you using a totally vanilla standard install?

Given the timing, this is most likely related to a data-explorer change which caused some issues. We’ve now reverted it, so if you try the rebuild again it should work better [image] Data explorer taking instance down on rebuild Self-hosting I see that has been reverted: https://github.com/discourse/discourse-data-explorer/commit/0f6b30c2d84d44978be1c845267609446ca9dbf2 I’ve been able to successfully rebuild now - thank you for getting onto that so promptly!

Yes, I’m using data explorer. I didn’t do a git pull before restarting. When I do a git pull, and then ./launcher restart app it’s not fixed. [image] Robert: Are you using a totally vanilla standard install? Except that I’m running it behind an nginx on the host. (And I have a few plugins, such as data explorer.) I’m now trying ./launcher rebuild app - I hope that rebuilding the app will preserve my forum’s database … and I’m not ending up with my forum reset. Doing launcher rebuild app does not address the issue. [image] Robert: This looks similar? This post describes an issue with privileged vs unprivileged containers, but doesn’t provide more information. It’s also from 2 years ago so may not be related to a recent update.

[image] Godmar Back: I’m now trying ./launcher rebuild app - I hope that rebuilding the app will preserve my forum’s database … and I’m not ending up with my forum reset. Sure, the database is on the mounted shared folder so persists. Restarting the container after a git pull is unlikely to be enough.

[image] Robert: Restarting the container after a git pull is unlikely to be enough. Got it. I also ./launcher rebuild app - would that not pull updates to the plugins?

Yep, that will update the plugins too (so long as they are cloned within app.yml)

In case this is still being investigated I had a 502 gateway error but not directly after the update routine which failed midway with a Ruby versioning error. Since I had not updated the server in about six weeks I ran apt update/upgrade and rebooted. That’s when the 502 error occurred, I could not raise the forum website. Rebuilding app fixed things and also updated Discourse fully. For the record I have these plugins installed and enabled: discourse-bbcode discourse-data-explorer discourse-docs docker_manager styleguide and these installed but disabled: discourse-topic-list-previews discpage

How to track down failure of discourse upstream inside container resulting in 502 Bad Gateway

Product Support Self-hosting

merefield (Robert) February 23, 2023, 8:57pm 5

Sure, the database is on the mounted shared folder so persists.

Restarting the container after a git pull is unlikely to be enough.

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How to track down failure of discourse upstream inside container resulting in 502 Bad Gateway

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