[clug] "Neighbour table overflow"

[Matthew Hawkins]

Kim Holburn said:
> At 4:15 PM +1100 2003/10/28, Matthew Hawkins wrote:
>>Kim Holburn said:
>>> At 1:58 PM +1100 03/10/28, Matthew Hawkins wrote:
>>>>Umm.. you can increase the size of the table via a /proc entry.
>>>
>>> Which one?
>>
>>/proc/sys/net/ipv4/neigh/default/gc_thresh3
>
> I read somewhere that you need to have:
> gc_thresh3  > gc_thresh2 > number of entries

Well, that should probably be gc_thresh3 > gc_thresh2 > gc_thresh1 >
number of entries.

You'll want to look at modifying all three.

And no, I don't *think* 3 subnets on two networks is enough to fill the
default cache sizes, as from memory the default is something in the range
of thousands.  I don't have a Linux box handy to check though :~(

I started playing with increasing these cache sizes until I maxed one out
and still had the neighbour table overflow problem (albeit it took a lot
longer to occur) and the dud route was discovered.  Fixing the real cause
solved the issue.

-- 
Matt