Autopause fails (eth0 not found, but exists)

[marcso-bdrck]

Autopause fails because eth0 is not found in /sys/class/net/ (only the host side vethXXXX):

[init] Autopause functionality enabled
[Autopause loop] Selected interface "eth0" does not exist!
[Autopause loop] Available interfaces within the docker container:
[Autopause loop]   bonding_masters lo vethe5e4612

The problem is that ifconfig shows eth0.
I'm not a Docker expert, but something seems to have changed with the handling of sysfs. I set up Docker on Ubuntu 22.04 yesterday. Every container shows the same behaviour.

Any ideas?

[itzg]

Providing your container config will probably help for people to answer.

[marcso-bdrck]

Yes I can imagine, it's a problem that rarely occurs. I think I've been able to narrow down the issue: My hosting service uses Virtuozzo for the vservers. There seems to be some kind of incompatibility causing the vethXXXX label in the container's sys-folder.

But nevermind, thanks for fixing my issue! :)

[itzg]

Nothing like a good edge case to shake out all the bugs 😉

[marcso-bdrck]

@itzg I'm very sorry but I've found a "bug" in the new implementation:

I think alpine's ifconfig doesn't know argument -s. So ifconfig -s | tail +2 | cut -f1 -d ' ' breaks down f.e. for image itzg/minecraft-server:java8.

root@XXXX:~# docker run -it --rm --entrypoint ifconfig itzg/minecraft-server -s
Iface      MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0      1500        2      0      0 0             0      0      0      0 BMRU
lo       65536        0      0      0 0             0      0      0      0 LRU
root@XXXX:~# docker run -it --rm --entrypoint ifconfig itzg/minecraft-server:java8 -s
ifconfig: -s: error fetching interface information: Device not found

[itzg]

Sorry about that. I'll rework it.

Honesty the alpine images are effectively deprecated since they have too many non-compliant behaviors...like what you found.

[marcso-bdrck]

I completely overlooked that there are other java8 images. I just use java8-multiarch on Ubuntu. Thank you for everything!