[SOLVED] Centos 7 NetworkManager does not read subinterfaces

ilesterg · 06-05-2018, 12:58 AM

Hello!

I have a Centos 7.4 setup with NetworkManager handling the networking, and I can't do the usual "systemctl disable NetworkManager; systemctl enable network" because of company restrictions.

Anyway..I was trying to add a sub-interface using nmtui, and I was able to. However, it needed a server restart to take effect. restarting or reloading the NetworkManager service doesn't add the sub interfaces.

The following don't work either:

Code:

nmcli connection reload
nmcli connection load /etc/sysconfig/network-scripts/ifcfg-ens160

Any idea how to bring the sub interfaces online without rebooting the server?

TIA.

MensaWater · 06-05-2018, 07:37 AM

You could just try:
ifup <sub-interface>
(e.g. ifup eth2:1 or ifup em1:1)

If that doesn't work:
ifdown <interface>;ifup <interface>
Where interface is the primary interface to which you added a sub-interface. (e.g. eth2 if your sub is eth2:1)

Typically it will bounce the interface fast enough that you won't lose connection even if you're on that interface when running the command. However, it is a good idea to be logged in via console or an alternate interface "just in case".

ilesterg · 06-05-2018, 09:50 PM

Quote:

Originally Posted by MensaWater

You could just try:
ifup <sub-interface>
(e.g. ifup eth2:1 or ifup em1:1)

If that doesn't work:
ifdown <interface>;ifup <interface>
Where interface is the primary interface to which you added a sub-interface. (e.g. eth2 if your sub is eth2:1)

Typically it will bounce the interface fast enough that you won't lose connection even if you're on that interface when running the command. However, it is a good idea to be logged in via console or an alternate interface "just in case".

Thank you very much!

Any idea why NetworkManager does not handle that? I also noticed that even stopping NetworkManager does not bring the network down, in contrast to the behavior of network service in CentOS/RHEL6 and earlier.

Anyway.. for the benefit of others..

For NetworkManager-managed interfaces, this works.

Code:

ifdown <interface>;ifup <interface>

For legacy, this one works, no need to restart the network service contrary to what the internet says.

Code:

ifup <interface>:<subinterface>