Default route took 20s to display with 'route' command
 

I have 2 NIC bonded together:

# ifenslave bond0 eth0 eth1

When my eth0 is unplugged, the 'route' command took 20s to display the final route (ie. the default route). However, if eth1 is unplugged, the route command display the entire(including the default route) routing table almost instantly.

What could be the cause why it took much longer to display the default route when eth0 is unplugged?

PS. my network connectivity is down when eth0 is unplugged.

Please advise.

Thanks !

For bonded interfaces they inherit the MAC Address of the first slave. The intent of bonding is to do round robin allocation of network traffic and thereby increase bandwidth. It is not a failover mechanism. If the NIC for which the MAC address of the bonded interface is down it really isn't sending the packet anywhere.

Your delay in seeing route is likely because it is trying to talk to the down NIC, timing out, then displaying the route table.

From the official howto, I have this description for bond=0 :

mode

Specifies one of the bonding policies. The default is balance-rr (round robin). Possible values are:

balance-rr or 0

Round-robin policy: Transmit packets in sequential order from the first available slave through the last. This mode provides load balancing and fault tolerance.

Seems that bond=0 does cater for fault tolerance (failover?) ?

Thanks !

Hi Akhran,

The route command tries to resolve the destination addresses using DNS. If your network is down or the DNS servers are unreachable, it shows the routing table with the ip numbers.

To prevent DNS resolution, use the "route -n".