>> Server runs with NetBSD 3.1. Applications we are using is Apache 2,
MySQL,
>> SpamAssassin,
>> ClamAV and mail and DNS services. It was working nearly 2 years without
>> problem.
>> I'm observing a network problem. Server doesn't permit network
connections
>> until reboot.

> When you says "doesn't permit network connections", what is the exact
> symptom ? Does the client gets a connection reset ? Does the
> connection time out ? Can you still ping the server ?

I don't know exactly how it happens. It's happening infrequently. Sometimes
one day, sometimes one hour later after boot, server becomes unresponsive.
I can't even ping the server.

While network stopped, "netstat -w 3"
 bge0 in       bge0 out              total in      total out
 packets  errs  packets  errs colls   packets  errs  packets  errs colls
 1797220  1884  2941122     0     0   1850096  2954  2990324     0     0
       0    11        0     0     0         0    17        2     0     0
       0     8        2     0     0         0    10        3     0     0
       0    12        3     0     0         0    15        3     0     0
       0    11        1     0     0         0    14        1     0     0

As you can see, all receiving packets are shown on "errs" column.

>> I can access server console and doesn't appear any error or warning.
>> "netstat -w 3" produced this output below: (We are using 512K bandwith)

> does 'dmesg' show anything unusual ?
> Also the outout of 'netstat -a -n' and 'netstat -m' could be usefull.

"dmesg" doesn't show anything unusual.
"netstat -a -n" shows few connection, naturally.
"netstat -m" shows:
1046 mbufs in use:
        810 mbufs allocated to data
        236 mbufs allocated to packet headers
76167 calls to protocol drain routines
^^^^^
Normally protocol drain routines is 0. This number increasing very fast
while network problem seen.

Additional info: Currently, ipf or pf or any other packet filter doesn't run
on server.