[Samba] Strange Bind freezing

[Daniel O'Connor]

> On 4 Dec 2021, at 17:51, Nikita Druba <admin at npo-lencor.ru> wrote:
> 
> 02.12.2021 7:50, Daniel O'Connor пишет:
>> 
>>> On 2 Dec 2021, at 16:16, Nikita Druba via samba <samba at lists.samba.org> wrote:
>>> 
>>> I  forgot to add, that config of new DC jail, zfs, named and samba fully the same as old DC and very similar for several other my samba DCs. I tried to switch on Internal DNS and back. I also tried to disable all Bind options, that no refers in samba wiki. I do not understand, where else I can found some information, what here is wrong.
>> I would try ktrace'ing the bind process, eg...
>> sudo -u bind ktrace -f /tmp/named.ktr named -g <rest of options>
>> 
>> Then reproduce and sift through the trace looking for bad things..
>> sudo kdump -f /tmp/named.ktr
>> 
>> Unfortunately ktrace is pretty low level (since it traces syscalls) but you might get a hint.
>> 
> I tried to collect some logs by ktrace and catched freeze moment. After last from usual log(when Bind freezing), in kdump starts many times repeating the next records:
> 
>  36460 named    CALL  nanosleep(0x7fffffffea30,0)
>  36460 named    RET   nanosleep 0
> 
> What can it means?  What do you thing - its a question of Bind or FreeBSD?

That just means it called nanosleep system call which is what usleep etc are implemented as.
Unfortunately ktrace is very low level so it can be hard to determine the context..

Something like truss or strace would provide a bit more context although they have a higher performance impact (probably not an issue for you).


--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
 -- Andrew Tanenbaum