On Thu, Sep 26, 2019 at 11:16:21AM +0200, Joerg Jung wrote:
> Hi,
>
> I run a few busy (~800 req/s) NSD servers which I upgraded
> to 6.5, all stock/default OpenBSD, e.g. I’ve not tweaked any
> sysctl values and nsd.conf matches the default as well, just
> added a few hundred zones.
>
> Now, when I increase servers from default 1 to 2 in nsd.conf:
> server-count: 2
> it starts spamming my log with:
> nsd[62723]: sendto 1.2.3.4 failed: Resource temporarily unavailable
>
> checking the source, server.c seems not to handle EAGAIN
> after sendto() and does not recover or retry, it just increases
> txerr statistic count - so answer seems really lost :(
>
> I tried higher debug level, as well as increasing socket buffers to:
> net.inet.udp.recvspace= 65536
> net.inet.udp.sendspace=65636
> but both didn’t help and netstat -s -p udp does show
> 0 dropped due to full socket buffers
> anyways. So, I don’t believe this is a socket buffer issue.
>
> The same server-count: 2 setting worked fine with 6.3.
>
> Any hints, insights, or pointers?
> Does anyone else experience the same?
>
> Thanks,
> Regards,
> Joerg
This is likely an fd limit issue. Try:
nsd:\
:openfiles=512:\
:tc=daemon:
in login.conf, followed by a restart of nsd.
-Otto
