I am trying to run an arm docker container on my x86 machine with the goal to eventually compile an application in a CI build. To my surprise it started out quite promising.
I set up qemu-arm-static on my machine (Manjaro Linux on 5.10 kernel) and ran the following to start up the container:
docker run --rm -it --platform linux/arm/v7 --dns 8.8.8.8 arm32v7/debian
I was greeted with a shell which was working as expected. I was able to run gcc for example for compiling a simple hello world. I was also able to use apt to install additional packages etc.
However when trying to run curl to fetch some data I am getting the following error:
root@2de7d98f3e31:/# curl --verbose github.com
* Expire in 0 ms for 6 (transfer 0x400598a0)
* Expire in 1 ms for 1 (transfer 0x400598a0)
* Expire in 4 ms for 1 (transfer 0x400598a0)
* Expire in 2 ms for 1 (transfer 0x400598a0)
* Expire in 5 ms for 1 (transfer 0x400598a0)
* Expire in 5 ms for 1 (transfer 0x400598a0)
* Expire in 4 ms for 1 (transfer 0x400598a0)
* Expire in 8 ms for 1 (transfer 0x400598a0)
* Expire in 8 ms for 1 (transfer 0x400598a0)
* Expire in 8 ms for 1 (transfer 0x400598a0)
* Expire in 10 ms for 1 (transfer 0x400598a0)
* Expire in 10 ms for 1 (transfer 0x400598a0)
* Expire in 8 ms for 1 (transfer 0x400598a0)
* Expire in 10 ms for 1 (transfer 0x400598a0)
* Expire in 10 ms for 1 (transfer 0x400598a0)
* Could not resolve host: github.com
* Expire in 14 ms for 1 (transfer 0x400598a0)
* Closing connection 0
curl: (6) Could not resolve host: github.com
nslookup also gives an error:
root@2de7d98f3e31:/# nslookup github.com
../../../../lib/isc/unix/net.c:595: probing sendmsg() with IP_TOS=b8 failed: No buffer space available
which to me looks like a more general error in the system, however all network related stuff like ping / curl with ip address / apt just work.
My /etc/resolv.conf shows
nameserver 8.8.8.8
as it could be expected when using the docker --dns option
Does anyone have an idea what is happening and what I could try next?
PS: DNS is working fine in non emulated x86 containers
