Hi!
The question in short:
I try to add a route over two interfaces with the "nexthop" option to
ip, but one of the gateways is always marked dead. How could that be?
Long story:
I have a testbed setup like the following picture:
+-----------------------------+
192.168.96.1/24 192.168.96.2/24
| |
192.168.112.0/20 -- Router A Router B --
192.168.64.0/20
| |
192.168.101.9/30 192.168.101.5/30
| |
192.168.101.10 - Router C - 192.168.101.6/30
Router C knows how to find 192.168.64.0/20 and 192.168.112.0/20, so I am
able to either set a route between these two networks over router C or
the direct link between A and B. That works perfectly.
But when I now try to add a route over both connections with equal cost
multipath, one of them is always marked dead.
on router A
ip r a 192.168.64.0/20 \
nexthop via 192.168.96.2 dev eth1 \
nexthop via 192.168.101.10 dev eth4
gives
192.168.64.0/20
nexthop via 192.168.96.2 dev eth1 weight 1
nexthop via 192.168.101.10 dev eth4 weight 1 dead
and the other way round
ip r a 192.168.64.0/20 \
nexthop via 192.168.101.10 dev eth4 \
nexthop via 192.168.96.2 dev eth1
gives
192.168.64.0/20
nexthop via 192.168.101.10 dev eth4 weight 1
nexthop via 192.168.96.2 dev eth1 weight 1 dead
Kernel is 2.4.17, all advanced routing options are turned on.
I just learned from
http://lists.nycwireless.net/pipermail/nycwireless/2001q4/001142.html
that equal cost multipath is broken in 2.4.13. Is that still true for 2.4.17?
Greetings
--
Robert Sander
Computer Scientist Epigenomics AG
Bioinformatics R&D www.epigenomics.com Kastanienallee 24
+493024345330 10435 Berlin
