Re: Bonding Driver Questions

From: Christopher E. Brown (cbrown@denalics.net)
Date: Tue Sep 26 2000 - 15:30:12 EST


On Sun, 24 Sep 2000, Constantine Gavrilov wrote:

> Hi, I'd like to use channel bonding driver for high availability.
>
> Currenly the bonding driver does not detect a dead slave link. When a
> slave link dies, it causes lots of network retransmits and the effective
> speed of the bonding device drops to almost zero. This has been verified
> in the lab.
>
> How difficult would it be to "teach" the bonding driver to check for the
> link status of its slave interfaces? Does ethernet layer provides a
> uniform way to check for the link status or it is adapter dependent?

        Ciscos solution to this involves 'KeepAlive' packets. They
default to on for a FastEtherChannel link, and each sub-interface
sends then every 10 seconds (default, configable), and expects to
receive them as well. If it does not it takes down the sub interface
until keepalives return.

        Unfortunately I have not been able to find any documentation on
the Cisco FastEtherChannel KeepAlive protocol, it would be nice to add
this to Linux Bonding. Its kind of a dirty fix, but it would fix link
state issues, and be compat with Cisco EtherChannel, Sun
EtherTrunking, and the Adaptec DuraLan bonding systems.

 ---
As folks might have suspected, not much survives except roaches,
and they don't carry large enough packets fast enough...
        --About the Internet and nuclear war.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sat Sep 30 2000 - 21:00:18 EST