/etc/rc.d/netif & em interfaces

Brian McCann bjmccann at gmail.com
Wed Dec 1 14:15:31 UTC 2010

On Wed, Dec 1, 2010 at 8:42 AM, Brian McCann <bjmccann at gmail.com> wrote:
> I'm having an interesting problem on a fresh 8.1-RELEASE1 install.
> I'll start by saying this didn't happen on 7.1 on the same exact
> machine.  I've been fighting with this for 2 days now and have come up
> with no answers on my own, so I'm hoping one of you guys can have some
> insight here.
> When I run "/etc/rc.d/netif restart" (also happens with a stop /
> start) , I can no longer get to the server over the network.  When I
> do a packet capture on my workstation, it looks like it's MAC address
> changed somehow.  The first two bytes of the address are different.
> For example, the real MAC is 00:15:17:1b:cf:7a , but I'll see the
> replies from a MAC of  "02:67:17:1b:cf:7a".  After each run of
> "/etc/rc.d/netif restart", the first two bytes will change again.  I
> have to reboot the server to get it working again.  The "em" cards in
> question are:
> dev.em.0.%desc: Intel(R) PRO/1000 Network Connection 7.0.5
> dev.em.0.%pnpinfo: vendor=0x8086 device=0x108c subvendor=0x8086
> subdevice=0x348d class=0x020000
> dev.em.1.%desc: Intel(R) PRO/1000 Legacy Network Connection 1.0.1
> dev.em.1.%pnpinfo: vendor=0x8086 device=0x1076 subvendor=0x8086
> subdevice=0x348d class=0x020000
> FWIW, this is on an Intel 1530 series server.
> Thanks in advance,
> --Brian

I botched the problem description slightly.  In the packet capture on
the workstation, the server's MAC is always correct.  The response
(SYN/ACK packet) from the server is destined to the wrong MAC address.
 The first two bytes are wrong somehow.  The arp table on the server
is correct.  If I run "arp -ad", the problem remains.

I've also produced this problem by doing "ifconfig em1 down" then
"ifconfig em1 up".

To make this problem even stranger, I can make a connection from the
server to a workstation without issue.  It appears to only be incoming

Thanks again,

Brian McCann

"I don't have to take this abuse from you -- I've got hundreds of
people waiting to abuse me."
                -- Bill Murray, "Ghostbusters"

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