Nextcloud hangs after fresh install (maybe related to NGINX reverse proxy)

[cruftex]

Steps to reproduce

1. Fresh Ubuntu 22.04
2. NGINX Proxy Setup from documentation
3. Fresh install of NC 26 with data dir on host: /mnt/ncdata
4. Open demo office documents: works
5. Open Photos: Connection is stuck, no answer from server
6. I can login again, and see the navigation, but as soon as I open something there is no answer

Expected behavior

Files open, directories got listed

Actual behavior

Connection is stuck

Host OS

Ubuntu 22.04

Nextcloud AIO version

Nextcloud AIO v6.2.1

Current channel

latest

Other valuable info

A hint where to start debugging, or whether I should try without NGINX reverse proxy first would be appreciated

[szaimen]

Hi, can you post the output of sudo docker logs nextcloud-aio-imaginary here?

[cruftex]

There is no log output. Here some more info:

root@fiji:~# docker logs nextcloud-aio-imaginary
root@fiji:~# docker exec -it nextcloud-aio-imaginary sh
~ $ netstat -l
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       
tcp        0      0 localhost:35337         0.0.0.0:*               LISTEN      
tcp        0      0 :::9000                 :::*                    LISTEN      
udp        0      0 localhost:40646         0.0.0.0:*                           
Active UNIX domain sockets (only servers)
Proto RefCnt Flags       Type       State         I-Node Path
~ $ ps
PID   USER     TIME  COMMAND
    1 nobody    0:11 imaginary -return-size -max-allowed-resolution 222.2
14657 nobody    0:00 sh
14663 nobody    0:00 ps
~ $ lsof -p 1
1       /usr/local/bin/imaginary        0       /dev/null
1       /usr/local/bin/imaginary        1       pipe:[124525]
1       /usr/local/bin/imaginary        2       pipe:[124526]
1       /usr/local/bin/imaginary        3       anon_inode:[eventpoll]
1       /usr/local/bin/imaginary        4       pipe:[126014]
1       /usr/local/bin/imaginary        5       pipe:[126014]
1       /usr/local/bin/imaginary        6       socket:[126030]
14657   /bin/busybox    0       /dev/pts/0
14657   /bin/busybox    1       /dev/pts/0
14657   /bin/busybox    2       /dev/pts/0
14657   /bin/busybox    10      /dev/tty
root@fiji:~# docker restart nextcloud-aio-imaginary
nextcloud-aio-imaginary
root@fiji:~# docker logs nextcloud-aio-imaginary
2023/07/11 08:31:59 Graceful shutdown
~ $ exit

I did reboot the server. After login the dashboard shows. When I click on Files the files show normally, when I click on Photos the connection hangs again.

root@fiji:~# free
               total        used        free      shared  buff/cache   available
Mem:         3907536     2334080      109036       90312     1464420     1214888
Swap:              0           0           0

I added 2GB of swap and restarted. Same problem.

Next, I disabled preview generation, via:

  'enable_previews' => false,

Now everything is reacting normally and clicking on Photos works without getting stuck.

So, something seems to be off with imaginary. What to try next?

[szaimen]

I'll move this to discussions for now since I cannot reproduce the issue.

[szaimen]

Can you disable imaginary temporarily and check if that fixes the issue for you?

[cruftex]

See my last post. I disabled "enable_preview" then everything seems to work

[szaimen]

See my last post. I disabled "enable_preview" then everything seems to work

Yes I saw this but it is a bad workaround. Did you try if only disabling imaginary also already makes it work?

[cruftex]

Yes I saw this but it is a bad workaround. Did you try if only disabling imaginary also already makes it work?

Ah! Sorry, I did not realise that is any different. Searching for imaginary in nextcloud and googling for disabling it did not yield any results. So I checked the config again and used common sense. I changed the config now to:

    6 => 'OC\\Preview\\Movie',
    7 => 'OC\\Preview\\Krita',
//    0 => 'OC\\Preview\\Imaginary',
  ),
  'enable_previews' => true,

Is this what I should do? With this setting, everything is "clickable" as well. No hangs.

[szaimen]

Is this what I should do?

No, the easiest way would have been to disable imaginary from the AIO interface.

With this setting, everything is "clickable" as well. No hangs.

I see. We have a fix scheduled for the next release which hopefully fixes the problem for you.

[cruftex]

@szaimen
I switched off imaginary via the AIO config and restarted. Strangely, I still get hangs related to the previews.
E.g. the request to /core/preview?fileId=38&x=250&y=250 does not get an answer.

I started digging and debugging a bit further.

What hangs now (or in general, see below) is OpenDocument preview generation.

Test 1: When I disable preview generation altogether, I can open OpenDocument files via Collabra.

Test 2: I enable preview generation and disable OpenDocument preview generation. Then, markdown and image previews are shown.

I am running out of time for today, next things to investigate:

I am running on 2 cores. The preview generation limits the parallel processes to 4 then. That means these would be exhausted when displaying the Dashboard since there are 5 open office files for demonstration. When clicking on Photos the preview requests will get stuck in the semaphore limiting the parallelism. My problem might be unrelated to Imaginary. So maybe I could switch imaginary on again, and keep OpenDocument preview generation off to test further.

The allowed parallelism depends on the cores. How many cores are you using for testing?

[szaimen]

My test server also has 2 cores.