[Nix-dev] Delays on ssh connection

[Carles Pagès]

It also happens if I ssh to localhost, so I don't think it's the same.
I forgot to mention that systemd is consuming a lot of cpu (top shows
~15% constantly).

2015-02-11 11:28 GMT+01:00  <emil.rangden at chas.se>:
> On 2015-02-11 9:57, Carles Pagès wrote:
>> Hi all,
>>
>> My system (nixos 14.12.231.139ead2) is in a state that, when
>> connecting through ssh there is a delay of ~30s. It happened to me a
>> while ago and was 'solved' with a reboot.
>>
>> Looking at the logs, I see:
>> feb 10 09:33:03 pica sshd[9346]: pam_unix(sshd:session): session
>> opened for user xxx by (uid=0)
>> feb 10 09:33:03 pica systemd-logind[1748]: New session 66 of user xxx.
>> feb 10 09:33:28 pica sshd[9346]: pam_systemd(sshd:session): Failed to
>> create session: Connection timed out
>>
>> Also, the log is full of:
>> feb 10 09:33:04 pica systemd[1]: Looping too fast. Throttling
>> execution a little.
>>
>> Seems like there is something wrong with systemd. Trying to look for
>> an explanation, I've found people commenting on similar issues that
>> were triggered by systemd crashes, but not exactly what I see.
>>
>> Going back in the log, the 'throttling' starts to appear after this:
>> feb 09 02:15:01 pica
>> /nix/store/8xg2yyyj651nik95lqmwza4xn0h7d7na-cron-4.1/bin/cron[24928]:
>> (root) CMD (/nix/store/8iq0r1d7na-cron-4.1/bin/cron[24928]: (root) CMD
>> (/nix/store/8iq0r1l97dzcsvkv33zg465gxlsx56dl-systemd-217/bin/systemctl
>> start ul97dzcsvkv33zg465gxlsx56dl-systemd-217/bin/systemctl start
>> update-locatedb.service)
>>
>> Though there's previous executions of that cron task that didn't
>> trigger the issue.
>>
>> Any clues on what might be wrong and/or how to solve this?
>> _______________________________________________
>> nix-dev mailing list
>> nix-dev at lists.science.uu.nl
>> http://lists.science.uu.nl/mailman/listinfo/nix-dev
>
> Might not at all be what you are looking for, but I had a similar
> problem
> with nixos-containers. It was 'solved' by telling sshd not to do any dns
> lookups with something like
>
>    services = {
>      openssh = {
>        enable = true;
>        extraConfig =
>          ''
>            UseDNS no
>          '';
>    };
>
> _______________________________________________
> nix-dev mailing list
> nix-dev at lists.science.uu.nl
> http://lists.science.uu.nl/mailman/listinfo/nix-dev