Re: wm0 and status discovery

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

On Tue, 8 Apr 2008 22:16:54 +0200
Joel CARNAT <joel%carnat.net@localhost> wrote:

> Hello,
> 
> I'm playing with ifwatchd on my laptop and have issue when connecting
> the LAN cable back. The idea is use wireless when LAN is not connected
> and back to LAN precedence when it is plugged.
> 
> I first though ifwatchd could cause this behaviour so I stopped
> everything (ifwatchd, dhclient, wpa_supplicant, ntpd, ...).
> 
> With the cable plugged-in, I get:
> wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>       
> capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx,TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
>       enabled=0
>       address: 00:15:58:86:c1:78
>       media: Ethernet autoselect (100baseTX
> full-duplex,flowcontrol,rxpause,txpause)
>       status: active
>       inet 10.15.5.24 netmask 0xffffff00 broadcast 10.15.5.255
>       inet6 fe80::215:58ff:fe86:c178%wm0 prefixlen 64 scopeid 0x1
> 
> When I unplug the cable, I get:
> wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>       
> capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx,TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
>       enabled=0
>       address: 00:15:58:86:c1:78
>       media: Ethernet autoselect (none)
>       status: no carrier
>       inet 10.15.5.24 netmask 0xffffff00 broadcast 10.15.5.255
>       inet6 fe80::215:58ff:fe86:c178%wm0 prefixlen 64 scopeid 0x1
> 
> When I plug the cable back, nothing happens - the NIC is still in
> "status: no carrier". The only way to get my carrier back is to issue
> an "ifconfig down ; ifconfig up".
> 
> I'm running 4.99.55/i386 on a Lenovo R61 and the NIC is:
> wm0 at pci0 dev 25 function 0: Intel i82801H (M) LAN Controller, rev.
> 3 wm0: interrupting at ioapic0 pin 20 (irq 11)
> wm0: PCI-Express bus
> wm0: FLASH
> wm0: Ethernet address 00:15:58:86:c1:78
> igphy0 at wm0 phy 1: i82566 10/100/1000 media interface, rev. 0
> 
> Is this an expected behaviour ?
> 
I've been noticing the same thing.  It seems to be recent behavior; I
first started noticing it a few weeks ago, as far as I can tell.

As for your underlying question -- I've been meaning to try
http://www.feyrer.de/NetBSD/bx/blosxom.cgi/nb_20070816_1133.html
but haven't had the cycles.


                --Steve Bellovin, http://www.cs.columbia.edu/~smb