Apr 2021

I was having some issues with Teaming interfaces being able to ping outside of the local LAN. When I started to look at the issue I noticed a lot of routes for local addresses that I had not configured.

To see the routes just use:

  ip route

When doing this I observed the following:

ip route

default via 192.168.1.1 dev mngt
10.0.0.0/8 dev eth2 proto kernel scope link src 10.0.154.2
10.0.0.0/8 dev eth3 proto kernel scope link src 10.0.154.3
11.0.0.0/8 dev eth4 proto kernel scope link src 11.0.154.4
11.0.0.0/8 dev eth5 proto kernel scope link src 11.0.154.5
169.254.0.0/16 dev eth2 scope link metric 1002
169.254.0.0/16 dev eth3 scope link metric 1003
169.254.0.0/16 dev eth4 scope link metric 1004
169.254.0.0/16 dev eth5 scope link metric 1005
169.254.0.0/16 dev mngt scope link metric 1008

So the default root is fine (via mngt) mngt is my team for the two management interfaces (eth0 and eth1). The rest of the interfaces (eth2-eth5) are for data and are not teamed.

What concerned me was the list of 169.254.0.0 addresses on eth2, eth3, eth4 and eth5. These interfaces have static addresses, dhcp is not configured and the DEFROUTE is set to no.

To be honest, I don't think they were causing any issues, but I wanted them gone, so here is what we did.

I wasn't able to remove the routes by using ip route del so the method used was as follows:

Edit the file /etc/sysconfig/network (it's probably empty)

Add the line NOZEROCONF=yes to the file and save and exit

Now reboot the server.

After this, performing an ip route shows the following:

ip route

default via 192.168.1.1 dev mngt
10.0.0.0/8 dev eth2 proto kernel scope link src 10.0.154.2
10.0.0.0/8 dev eth3 proto kernel scope link src 10.0.154.3
11.0.0.0/8 dev eth4 proto kernel scope link src 11.0.154.4
11.0.0.0/8 dev eth5 proto kernel scope link src 11.0.154.5
192.168.1.0/24 dev mngt proto kernel scope link src 192.168.1.154

All of the 169.254.0.0 reference are gone.