Question regarding network bond config

[Oggy512]

Hi folks,
I'm fairly new to Proxmox, but it seems to be a nice product for my usecase. I have a question regarding the network configuration.

Ony my server I have two NICs, eno1 and eno2. I'd like to bond them via LACP to have a fault-tolerance and to increase the speed to 2 GBit/s.

I read the https://pve.proxmox.com/wiki/Network_Configuration wiki article, but still, I'm not getting it at all.

What is the differenct between the both mentionend configs?
In the first example we set an IP address to the bond and another one to the bridge, but in the bridge we include just one interface. Where is then the added value form the bond? If eno1 is down, there is to fault-tolerance on the bridge and even is eno1 is up there is just 1 GBIt/s?

In the secon example we create a bond and include that bond in the bridge, where we set an IP address. That would make from a logical perspective sense for me, but the description in the wiki is different. Can someone explain that to me?

Thx!

Cfg 1)

auto lo
iface lo inet loopback

iface eno1 inet manual

iface eno2 inet manual

auto bond0
iface bond0 inet static
      slaves eno1 eno2
      address  192.168.1.2
      netmask  255.255.255.0
      bond-miimon 100
      bond-mode 802.3ad
      bond-xmit-hash-policy layer2+3

auto vmbr0
iface vmbr0 inet static
        address  10.10.10.2
        netmask  255.255.255.0
        gateway  10.10.10.1
        bridge-ports eno1
        bridge-stp off
        bridge-fd 0

Cfg2)

auto lo
iface lo inet loopback

iface eno1 inet manual

iface eno2 inet manual

auto bond0
iface bond0 inet manual
      slaves eno1 eno2
      bond-miimon 100
      bond-mode 802.3ad
      bond-xmit-hash-policy layer2+3

auto vmbr0
iface vmbr0 inet static
        address  10.10.10.2
        netmask  255.255.255.0
        gateway  10.10.10.1
        bridge-ports bond0
        bridge-stp off
        bridge-fd 0

 

[wolfgang]

Hi,

to increase the speed to 2 GBit/s.

This does not work with LACP. You can increase the bandwidth to 2GB but the speed is always 2 x 1GBit.

The first version is wrong.
Thanks for pointing to this.

the vmbr0 bridge-port must be another nic like eno3.

 

[Oggy512]

If the vmbr0 then has eno3, instead of eno1 or 2 or bond0, then it would have a failover, in case bond0 (both links) breaks down, however it would need a reconnect, using the second IP, right?
So in that case, the PVE host is accessible with 2 IPs?

 

[wolfgang]

however it would need a reconnect, using the second IP, right?

Yes, correct.

So in that case, the PVE host is accessible with 2 IPs?

Yes, correct.

 

[Magneto]

Hi,


This does not work with LACP. You can increase the bandwidth to 2GB but the speed is always 2 x 1GBit.

The first version is wrong.
Thanks for pointing to this.

the vmbr0 bridge-port must be another nic like eno3.

So how does one get 2Gb speed across 2 NIC's?

 

[ph0x]

You don't.
Two clients can saturate 1G each, but that's it.
Even with round robin you won't be better off, since this induces a lot of overhead because of retransmitted packets etc.