[SOLVED] Swap a 1 NIC PCI with a 2 NIC PCI

[trigg3r]

I have a 2 sever PVE cluster. Both have 3 NIC: eth0 for corosync, eth1 for VMs storage and for backup traffic and eth2 for LAN connection. I want to add one more NIC to separate storage and backup traffic but one server doesn't has an available PCI slot. So I'm planin to buy a new PCI with 2 NIC. What I'm asking for is: what's problem for the PVE NIC configuration when I swap the current 1 NIC PCI card with the new 2 NIC PCI card?

 

[Stoiko Ivanov]

This depends on a few things:
* If you've set up the PVE-Node before predictable network-names (i.e. your nics are still called eth0, eth1, eth2 ....) - you need to edit the udev-file (/etc/udev/rules.d/70-....rules - don't exactly remember the snippet name) where the nics get their index based on the mac-address.
* If your system uses predictable network-interface names (see [0] - i.e. your nics are called eno1, enp1s2f3,...) - there are (sadly) two possible outcomes:
* your original nic-name is then taken by one of the two ports and you don't need to do anything (apart from plugging cable into the right port) and have a new interface available and unused
* the nics get renamed and you need to do a match from old to new names (ethtool -p <nicname> can help)

In any case do make sure that you have access to the box when doing this (if you do the swap yourself that's given, but if it's in a datacenter make sure you have a IPMI, or remote console)

I hope this helps!


[0] https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

 

[trigg3r]

I hope this helps!

Yes, a lot! Now I'm going to do the job with more confidence knowing where problems can arise. Thanks.

 

[Stoiko Ivanov]

You're welcome - Good luck with the swap!

 

[trigg3r]

Everything went fine, but ...

you need to edit the udev-file

One of the two PVE servers has NIC names sets in /etc/udev/rules.d/70-persistent-net.rules. So I add a row for the new NIC:

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="xx:xx:xx:xx:xx:xx", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="xx:xx:xx:xx:xx:xx", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="xx:xx:xx:xx:xx:xx", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth2"
# THE NEW ONE
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="xx:xx:xx:xx:xx:xx", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth3"

But after reboot it is renamed:

dmesg | grep eth

[    1.017832] r8169 0000:08:00.0 eth0: ...
[    1.018153] r8169 0000:08:01.0 eth1: ...
[    1.018500] r8169 0000:08:02.0 eth2: ...
[    1.062249] r8169 0000:08:00.0 enp8s0: renamed from eth0
[    1.266156] e1000e 0000:00:1f.6 eth0: ...

it seem that, for some reason, /etc/udev/rules.d/70-persistent-net.rules does not works ...

 

[trigg3r]

Ok ... I forget to run:

update-initramfs -u

 

[Stoiko Ivanov]

did it work out after running `update-initramfs -k all -u`? - If yes please mark the thread as 'SOLVED'
Thanks!