>> one of our unbound hosts recently exited, and before it did, it
>> logged this:
>>
>> Sep 19 14:25:56 xxx unbound: [96:4] error: tube msg write failed:
>> Resource temporarily unavailable
>> Sep 19 14:25:56 xxx unbound: [96:4] fatal error: could not write stat
>> values over cmd channel
>
> The error is on a pipe between unbound processes (threads). It should
> not be out of resources (it might block of course, waiting for them, and
> blocking pipes are not a problem for unbound, but this error is like a
> pipe randomly breaks up).
This turned out to be caused by us running a too old version of
unbound, version 1.5.4. I've since upgraded to 1.5.9, so this
exact problem should not happen again for us. In-between there,
tube_write_msg() grew a test for EAGAIN (causing a retry) in the
non-blocking case.
Regards,
- Håvard
