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The Basics
- Nextcloud Server version (e.g., 29.x.x):
AIO 12.2.1
- Operating system and version (e.g., Ubuntu 24.04):
Ubuntu 24.04
- Reverse proxy and version _(e.g. nginx 1.27.2)
Caddy
- Is this the first time you’ve seen this error? (Yes / No):
Yes
- When did this problem seem to first start?
after sudo apt update / upgrade
- Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
AIO Docker
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
no
Summary of the issue you are facing:
I used the Nextcloud AIO interface for some files (system was working fine) and thereafter routinely logged into server and performed a apt update && apt upgrade. No docker file update was made.
After system restart (new kernel), all docker services are back, except Nextcloud main login. I get a 502. I can call up 8080, and it asks for passphrase - I can log in and it shows all container running green. The other services (immich, etc) are running fine, it’s just nextcloud that is unreachable: I am clueless where to go hunting.
I can see that Apache service is working: sudo docker exec -it nextcloud-aio-apache bash -x /healthcheck.sh
nc -z nextcloud-aio-nextcloud 9000Connection to nextcloud-aio-nextcloud (172.19.0.7) 9000 port [tcp/*] succeeded!
nc -z 127.0.0.1 8000Connection to 127.0.0.1 8000 port [tcp/*] succeeded!
nc -z 127.0.0.1 11000Connection to 127.0.0.1 11000 port [tcp/*] succeeded!
Logs of Caddy show I think that caddy can’t find nextcoud-aio-apache properly?
{"level":"error","ts":1766005148.6982927,"logger":"http.log.error","msg":"dial tcp: lookup nextcloud-aio-apache on 127.0.0.11:53: server misbehaving","request":{"remote_ip":"1xx.1xx.250.87","remote_port":"54911","client_ip":"1xx.1xx.250.87","proto":"HTTP/1.1","method":"GET","host":"cloud.xxx.xx","uri":"/index.php/apps/files/preview-service-worker.js","headers":{"Cookie":["REDACTED"],"X-Forwarded-For":["93.104.89.211"],"Connection":["keep-alive"],"Dnt":["1"],"Cache-Control":["max-age=0"],"Sec-Fetch-Dest":["serviceworker"],"User-Agent":["Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36"],"Accept-Language":["en-GB,en-US;q=0.9,en;q=0.8,de;q=0.7,fr;q=0.6"],"Service-Worker":["script"],"Sec-Fetch-Mode":["same-origin"],"Referer":["https://cloud.ingels.eu/index.php/apps/files/preview-service-worker.js"],"Accept-Encoding":["gzip, deflate, br, zstd"],"Accept":["*/*"],"Sec-Fetch-Site":["same-origin"]},"tls":{"resumed":false,"version":772,"cipher_suite":4865,"proto":"","server_name":"cloud.ingels.eu"}},"duration":0.001858637,"status":502,"err_id":"irudsevui","err_trace":"reverseproxy.statusError (reverseproxy.go:1390)"}
Log entries & Caddyfile / Docker files
Apache docker Logs
Connection to nextcloud-aio-nextcloud (172.19.0.7) 9000 port [tcp/*] succeeded!
/usr/lib/python3.12/site-packages/supervisor/options.py:13: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.
import pkg_resources
{"level":"info","ts":1765937055.1066477,"msg":"maxprocs: Leaving GOMAXPROCS=4: CPU quota undefined"}
{"level":"info","ts":1765937055.1070461,"msg":"GOMEMLIMIT is updated","package":"github.com/KimMachineGun/automemlimit/memlimit","GOMEMLIMIT":5591737958,"previous":9223372036854775807}
{"level":"info","ts":1765937055.1070848,"msg":"using config from file","file":"/tmp/Caddyfile"}
[Wed Dec 17 03:04:15.108483 2025] [mpm_event:notice] [pid 42:tid 42] AH00489: Apache/2.4.66 (Unix) configured -- resuming normal operations
[Wed Dec 17 03:04:15.108583 2025] [core:notice] [pid 42:tid 42] AH00094: Command line: '/usr/local/apache2/bin/httpd -D FOREGROUND'
{"level":"info","ts":1765937055.1110933,"msg":"adapted config to JSON","adapter":"caddyfile"}
{"level":"info","ts":1765937055.1172836,"msg":"serving initial configuration"}
Configuration
Caddy
main system caddyfile
{
# email to use on Let's Encrypt
email sysadmin@xxxx
}
cloud.xxxxx.xx {
header Strict-Transport-Security max-age=31536000;
reverse_proxy nextcloud-aio-apache:11000
}
Caddy docker file
services:
caddy:
image: caddy:alpine
restart: always
container_name: caddy
ports:
- "80:80" # Publish Caddy's HTTP port to the host
- "443:443" # Publish Caddy's HTTPS port to the host
volumes:
- ./Caddyfile:/etc/caddy/Caddyfile
- ./certs:/certs
- ./config:/config
- ./data:/data
- ./sites:/srv
# network_mode: "host"
networks:
- app_net
networks:
app_net:
external: true
Nextcloud docker file
services:
nextcloud-aio-mastercontainer:
image: nextcloud/all-in-one:latest
init: true
restart: always
container_name: nextcloud-aio-mastercontainer
volumes:
- nextcloud_aio_mastercontainer:/mnt/docker-aio-config
- /var/run/docker.sock:/var/run/docker.sock:ro
ports:
- 8080:8080
networks:
- app_net
environment:
APACHE_PORT: 11000
APACHE_IP_BINDING: 0.0.0.0
APACHE_ADDITIONAL_NETWORK: app_net
volumes:
nextcloud_aio_mastercontainer:
name: nextcloud_aio_mastercontainer
external: true
networks:
app_net:
external: true
Thanks for your help!