Podman container cannot reach another containers port on same host (after upgrade from f38 to 40)

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Hi there, i update my server from f38 over f39 to f40 today,
Now my apache2-container for reverse-proxy to some nextcloud- and other web-containers cannot reach these pods anymore as before.

e.g. i have a container on port 8018 running some spring-boot-web-things
i can reach it with http://server-ip:8018 fine

but my apache cannot curl into it, whereas i can do it as user or from another machine.
Here ist the (untouched since f38) apache-conf-part:

<VirtualHost *:443>
  ServerName my-app.server.tld
  ProxyPass        /  http://http:8018/
  ProxyPassReverse /  http://http:8018/
</VirtualHost>

from my workstation:

curl -v 192.168.x.x:8018
*   Trying 192.168.x.x:8018...
* Connected to 192.168.x.x (192.168.x.x) port 8018
> GET / HTTP/1.1
> Host: 192.168.x.x:8018
> User-Agent: curl/8.6.0
> Accept: */*
...

and on the server:

me@s47:$ podman exec -it http bash
[root@36be467ebefd /]# curl -v 192.168.x.x:8018
*   Trying 192.168.x.x:8018...
* connect to 192.168.x.x port 8018 from 192.168.x.x port 55996 failed: Connection refused
* Failed to connect to 192.168.x.x port 8018 after 0 ms: Couldn't connect to server
* Closing connection
curl: (7) Failed to connect to 192.168.x.x port 8018 after 0 ms: Couldn't connect to server
[root@36be467ebefd /]# 
exit
me@s47:~$ curl -v 192.168.x.x:8018
*   Trying 192.168.x.x:8018...
* Connected to 192.168.x.x (192.168.x.x) port 8018
> GET / HTTP/1.1
> Host: 192.168.x.x:8018
> User-Agent: curl/8.6.0
> Accept: */*
...

so what can i do?
i already tried

sysctl -w net.ipv4.ip_forward=1
sysctl -p

but with no luck.

–
greetings
sebseb

1 Like
2

i got help on Kiwi IRC

i now added the line
–net=slirp4netns:allow_host_loopback=true,port_handler=slirp4netns

to my apache2-reverse-proxy container and all to all the nextcloud-pods, and it is working again. (there might be an issue with podman5 and pasta, so slip4netns helped here)

this can be closed.