problems with network on em

Jeremy Chadwick freebsd at
Sat Nov 20 15:54:35 UTC 2010

On Sat, Nov 20, 2010 at 05:09:28PM +0200, rolnas at wrote:
> I'm experiencing network interface stalls on em in FreeBSD 8.1-RELEASE (-p1).
> It looks like the problem could be solved in 8-STABLE, but should I upgrade to it ?
> Is it OK to try to get only em driver code and recompile as module and try to run it ?
> sysctl dev.em.2.stats=1:
> ...
> em2: Missed Packets = 101334
> em2: Receive No Buffers = 488
> ...
> em2: RX overruns = 1356
> em2: watchdog timeouts = 1
> ...
> Only "ifconfig em2 down;ifconfig em2 up" helps for some time.
> The same happens on em0 interface only, but not in the same time.
> It is production (NAT) router with pf+pfsync+carp and failover over another router.
> They are old "SunFire X4100" boxes (4GB RAM, 2*2 AMD Opteron 2.2GHz).

You're going to need to provide output from the following, run as root.
For the pciconf command, please only include the entry that's relevant
to the device in question (em2).  You can also XXX-out the MAC address
and/or IP addresses if you're worried about security.

$ pciconf -lvc
$ dmesg | grep em2
$ sysctl dev.em.2
$ uname -a
$ netstat -ind -I em2


| Jeremy Chadwick                                   jdc at |
| Parodius Networking              |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |

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