Inconsistent DNS resolution about static-ffmpeg HOT 13 CLOSED

Just came across this recently: https://martinheinz.dev/blog/92

from static-ffmpeg.

... and of course come back to wader/static-ffmpeg once alpine uses the new musl version :)

from static-ffmpeg.

@Jocaru hey again, master should support dns over tcp now

from static-ffmpeg.

Hi, yes ffmpeg relay on the OS, musl libc in case of static-ffmpeg, to resolve. Do you know dig has it's own DNS implementation or uses libc?

The only thing that comes to mind is https://github.com/wader/static-ffmpeg#i-see-name-does-not-resolve-errors-for-hosts-that-should-resolve that musl libc does not support DNS over TCP. When you do dig do you see a lot of answers sometimes? or maybe it's possible to see if dig swaps to using TCP?

from static-ffmpeg.

Yeap same issue think. The I/O error is a bit confusing but i've seen before that ffmpeg has code that mixes up sometimes what the underlaying error actually was so would not surprise me.

BTW i got curious about the state of musl and DNS over TCP, it looks like it's coming in musl 1.2.4 https://gitlab.alpinelinux.org/alpine/tsc/-/issues/43
https://git.musl-libc.org/cgit/musl/commit/?id=51d4669fb97782f6a66606da852b5afd49a08001

from static-ffmpeg.

Quick look at the bind-utils code it do seem to have it's own DNS implementation, which makes sense i guess if it's part of bind :)

from static-ffmpeg.

@Jocaru did you figure something more about? seems to be DNS?

from static-ffmpeg.

@wader no, I still have the problem sometimes. I have read the link that @binoculars sent and that may be the problem I guess. The domains I use in my ffmpeg command are CNAMEs to another one and there are also redirections and that may be the problem (because of musl). I guess I should just use Debian or Ubuntu instead of Alpine.

I'm also just using your ffmpeg executable outside of your container (in another container). I did a quick test in a Ubuntu container but couldn't execute it. I ended up using yours because it has all libraries that I need (I must use the -cenc_decryption_key option).

I don't know if it's much asking, but could you do an Ubuntu/Debian image?

from static-ffmpeg.

Aha i see. Problem with building glibc based static executables is that they will not be truely static and might up loading dynamic things, if i remember correctly the NSS stuff i dynamic. So would probably have to build per distro etc.

I do know of stripped down "forks" of this Dockerfile that build and run on ubuntu, is a bit of work to do but possible.

Another alternative might be to build with the musl DNS patches or build with master version of musl somehow.

A second alternative could be to run thru non-musl based http proxy or let the program that runs ffmpeg do DNS resolve and rewrite the URL to use IP:s (might require some host header trickery?), both ways hacky but might work.

How urgen is it to be fixed? i guess it will be some months until the DNS fixes are in alpine stable.

from static-ffmpeg.

Not urgent at all, I'm just using that for a personal project :)

from static-ffmpeg.

Okok! i thought -cenc_decryption_key was quite old but was added in 5.1 FFmpeg/FFmpeg@8b64d8d so maybe you can use some other image like https://github.com/linuxserver/docker-ffmpeg that seem be ubuntu-based and have 5.1+.

from static-ffmpeg.

Okok! i thought -cenc_decryption_key was quite old but was added in 5.1 FFmpeg/FFmpeg@8b64d8d so maybe you can use some other image like https://github.com/linuxserver/docker-ffmpeg that seem be ubuntu-based and have 5.1+.

Thank, I'll try that!

I think you can close this issue already, or if you want to keep it open until that new musl version comes out, up to you!

from static-ffmpeg.

@Jocaru hey again, master should support dns over tcp now

Thank you!

from static-ffmpeg.