[ale] detecting an unplugged network cable?

Bao Ha baoh at linuxwizardry.com
Mon Feb 19 10:59:24 EST 2001



The driver knows it.  It is recorded as a statistics of heart beat
error: stats.tx_heartbeat_error.  But I don't think the kernel is
using it for anything else.  If you turn on the debug level of 
the driver to a high enough level, you will see its complaints in 
the syslog.

You may want to grep the output of /proc/net/dev and look for
increases of carrier errors on the network interface.

Heart beat/link is only relevant to 10baseT/100baseTx.  How does
Windows do it for coaxial and thick ethernet?  Puting on my 
network engineering/support hat, it is not very useful except 
maybe in the laptop case where there is a lot of transient.  I 
believe the pcmcia  package does detect and report network loss.

Bao

> -----Original Message-----
> From: owner-ale at ale.org [mailto:owner-ale at ale.org]On Behalf Of
> hirsch at zapmedia.com
> Sent: Monday, February 19, 2001 10:16 AM
> To: ale at ale.org
> Subject: [ale] detecting an unplugged network cable?
> 
> 
> Is there any way to detect when a network cable gets unplugged?  My
> windows colleagues say that windows can tell within seconds of the
> cable being yanked that there is no network, but I can't.  The card is
> clearly aware of it, too, since the green light goes out, but I don't
> know how to check for the connection.  Is there a way?
> 
> Thanks,
> 
> Michael
> --
> To unsubscribe: mail majordomo at ale.org with "unsubscribe ale" 
> in message body.
> 

--
To unsubscribe: mail majordomo at ale.org with "unsubscribe ale" in message body.





More information about the Ale mailing list