crazy network problem -- sleep?

[Adrian Penisoara]

Hi,
2009/3/1 stutiredboy <stutiredboy at gmail.com>

> hi,all:
>
>        recently , we  found a problem that , some server which with FreeBSD
> 6.2 may stop networking after
> days of services, it is so difficulty express this status, e, such as
> sleep?  i can not ping this server, tracert is also
> failure, and other services ,network/server seems to be down... but
> while i insert the keyboard/mouse/crt in ,
> everything is ok, such as a ring to call the system to wake-up... no
> errors found in dmesg or /var/log/messages,
> such as nothing happened...orz，our unlimit args as follow:
>
> cputime      unlimited
> filesize     unlimited
> datasize     2088152 kbytes
> stacksize    65536 kbytes
> coredumpsize unlimited
> memoryuse    unlimited
> vmemoryuse   unlimited
> descriptors  655000
> memorylocked unlimited
> maxproc      5547
> sbsize       unlimited
>
> plz give me some suggestion to trace the problem or solve it . thanks a
> lot !
>

  First you need to check whether packets are reaching the system and
whether the response packets are leaving it with tcpdump(8) on the
appropriate interface.

  If you see the packets coming but not coming out then you need to check
the status of your TCP/IP stack -- e.g. post the output of "netstat -m" and
"netstat -s". Also check dmesg output for any errors.

  If you are using firewall(s) (ipfw/ipfilter/pf) then check the rules and
the firewall states status; try temporarily disabling the firewall (ipfw
disable firewall / ipf -D / pfctl -d) and check whether your system becomes
reachable.

  Check CPU load, interrupts, packet stats  (systat -vmstat / systat
-ifstat).

Regards,
Adrian Penisoara
EnterpriseBSD