Re: unbound EAGAIN sendto errors

On 29/04/2025 18:11, Otto Moerbeek wrote:
> On Tue, Apr 29, 2025 at 04:32:01PM +0300, Kapetanakis Giannis wrote:
>
>> Can it be related to this: dropped due to no socket?
> IIRC OpenBSD does handle sending to a non-blocking socket in the
> multi-threaded case very well. If multiple threads try to do that
> simulteneously, some of them will get a EAGAIN. To test this
> hypothesis, try running with a single thread and see if the errors
> disappear.
>
> -Otto

I did run one-thread and the errors where gone...

ok, how I can we go to multiple threads now without the errors?

Even with the one thread i still get dropped due to no socket on netstat

G

>
>> # netstat -ss|grep -A7 ^udp
>> udp:
>>         819120 datagrams received
>>         15494 with no checksum
>>         22621 dropped due to no socket
>>         170569 broadcast/multicast datagrams dropped due to no socket
>>         625930 delivered
>>         6497322 datagrams output
>>         341480 missed PCB cache
>>
>> G
>>
>> On 29/04/2025 15:36, Kapetanakis Giannis wrote:
>>> Hi,
>>>
>>> I'm having this busy router with multiple private networks behind which is also doing dns caching services.
>>> vlans and carp are also involved.
>>>
>>> I'm getting this almost every second on my logs from multiple/different vlans and IPs (had it also on 7.6 as well on 7.7 now).
>>>
>>> Apr 29 15:11:49 unbound: [18412:1] notice: remote address is 10.14.0.196 port 44886
>>> Apr 29 15:11:54 unbound: [18412:1] notice: sendto failed: Resource temporarily unavailable
>>>
>>> tcpdump on this shows:
>>> 15:11:49.420280 10.14.0.196.44886 > 10.14.0.1.domain: 13+ [2au] A? google.com.(74) (DF) [tos 0xe0]
>>> 15:11:52.519896 10.14.0.196.44886 > 10.14.0.1.domain: 13+ [2au] A? google.com.(74) (DF) [tos 0xe0]
>>> 15:11:52.520048 10.14.0.1.domain > 10.14.0.196.44886: 13 FormErr- 0/0/2(74)
>>>
>>> I believe I'm hitting some kind of limit either in the OS or in unbound.
>>>
>>> What I have and tested so far:
>>> kern.maxfiles=32768
>>>
>>> login.conf:
>>> unbound:\
>>>    :openfiles=32768:\
>>>    :tc=daemon:
>>>
>>> unbound.conf:
>>>    num-threads: 4
>>>    num-queries-per-thread: 4096
>>>    outgoing-range: 16384
>>>    so-rcvbuf: 2m
>>>    so-sndbuf: 2m
>>>
>>> no luck so far.
>>>
>>> pf states ~ 30K (hard limit 200K)
>>> load 1.2 (mostly by pmacctd)
>>> hw.machine=amd64
>>> hw.model=Intel(R) Xeon(R) CPU X5660 @ 2.80GHz
>>> hw.ncpu=6
>>>
>>> Any ideas?
>>>
>>> Thanks,
>>>
>>> G
>>>
>>>
>>>
>>>