"em" driver shuts down interface when "ifconfig media 100baseTX" is invoked

Tue Mar 20 08:30:27 UTC 2007

FreeBSD cg-gw 6.2-PRERELEASE FreeBSD 6.2-PRERELEASE #10: Tue Jan 16 01:40:27 EST 2007     root at taint:/usr/obj/usr/src/sys/FW-YQ  i386

I did:
"ifconfig em2 media 100baseTX mediaopt full-duplex"

ifconfig em2 now reports:
...
media: Ethernet 100baseTX <full-duplex> (autoselect)
status: no carrier

"ifconfig em2 media 100baseTX" also does this

We tried it on 2 different 100baseTX interfaces with the same result

"ifconfig em2 media autonegotiate" brings the interface back up

It doesn't seem to happen on another interface which autonegotiates
10baseT half-duplex, however

This seems to indicate there might be a driver problem since
the 2 interfaces connect to very different kinds of equipment

Any suggestions?