Multiple NICs on one LAN

[S3ntry69]

Hi All

Newbie question here. I have one ProxMox node with 2 x 1GB NICs and also 2 x 10GB NICs. One of the NICs is for the ProxMox management. This leaves me with 1 x 1GB and 2 x 10GB spare.
Can I create new Linux Bridge and associate the physical NICs to use the same network. so as an example. vmbr0 uses 192.168.x.1/24 with a gateway of 192.168.x.254 and then vmbr1 uses 192.168.x.2/24. So when I create a VM I can choose either bridge and it will be on the same network. My plan is also to have a Server 2022 VM that will be DHCP for the Domain.

Would this work?, hope it makes sense.

Thanks
Sean

 

[S3ntry69]

Or would it just be a case of not specifying the IP address when creating the bridge and then manually giving the VM a static IP after it is created?

 

[S3ntry69]

This example is how I have my old ESXi host configured. Can I create the same with Proxmox?

 

[shanreich]

I assume you want to do this because you want to use the bandwidth of all interfaces? In that case I suggest you bond the 10G NICs together via LACP (your switch needs to support that). Be careful with putting multiple unbonded NICs attached to the same switch on the same bridge, since you're basically creating a loop.

 

[S3ntry69]

I assume you want to do this because you want to use the bandwidth of all interfaces? In that case I suggest you bond the 10G NICs together via LACP (your switch needs to support that). Be careful with putting multiple unbonded NICs attached to the same switch on the same bridge, since you're basically creating a loop.

My switch doesnt support LACP. is there another way?

 

[shanreich]

We generally only recommend using LACP or active-backup as bond modes, since other bond modes can cause issues (particularly balance-tlb and balance-alb). If your switch supports static LAG, you could try using balance-xor, but since it's not standardized it depends on your available hardware.

Also note that even with 802.3ad or balance-xor a single connection can still only use one link, since it only provides load-balancing for multiple connections. So if all your connections are non-local and go through the same gateway, then both bonding modes will only utilize one link still. With 802.3ad there's the option of using layer3+4 as hashing policy, but that is actually also not part of the 802.3ad standard, and it can cause issues as well.

For more information see the kernel docs [1]

[1] https://www.kernel.org/doc/Documentation/networking/bonding.txt

 

[S3ntry69]

So is there any way at all to achieve the same resolution as I currently have below without having to use LACP or LAG?

 

[shanreich]

I don't really know much about ESXi, but judging from a quick glance of the documentation, you have to set up teaming (= bonding) for multiple NICs on a vSwitch as well. From what I can tell, the default policy does load balancing based on the originating virtual port. There's not really an equivalent setting currently available in the kernel bonding driver.