full socket buffers

Glenn Satchell glenn.satchell at uniq.com.au
Wed Feb 9 14:42:11 UTC 2011


On 02/10/11 00:40, Mirek Lauš wrote:
> On Wed, Feb 9, 2011 at 2:38 PM, David Forrest<drf at maplepark.com>  wrote:
>> On Wed, 9 Feb 2011, Mirek Lauš wrote:
>>
>>> According to this: http://www.29west.com/docs/THPM/udp-buffer-sizing.html
>>> the kern.ipc.maxsockbuf is the right oid. The problem only occurs after
>>> few days
>>> of dhcpd process running then it begins do drop UDP randomly forcing us to
>>> restart dhcpd process. Then everything goes well for few days again. Now
>>> I really don't know where to look for help.
>>>
>>> Regards,
>>> Miroslav
>>
>> Perhaps a cron job restarting dhcpd during an inactive time period every
>> couple days would stop the problem from affecting your users.
>
> Yes. But I don't like this solution because it is not a solution. It
> is a workaround.
> We would not be able to find the real cause of the issue.
>
> Regards,Miroslav

Is there any pattern, such as time of day when it occurs? Any other 
heavy network traffic at the time? Perhaps this is a symptom of some 
other issue? Have you confirmed with netstat -s that the number of 
packets dropped due to full socket buffers increases when the problem is 
apparent?

How about increasing the buffer size a bit further? 256k is pretty small 
by today's standards. In an earlier post you mentioned you tried 1MB, so 
perhaps try 2MB, then 4, maybe 8MB to see if that is sufficient.

The web page you refer to seems to explain the settings quite well.

-- 
regards,
-glenn
--
Glenn Satchell                            |  Miss 9: What do you
Uniq Advances Pty Ltd, Sydney Australia   |  do at work Dad?
mailto:glenn.satchell at uniq.com.au         |  Miss 6: He just
http://www.uniq.com.au tel:0409-458-580   |  types random stuff.



More information about the dhcp-users mailing list