Setting up a bridge?

Tundral

New Member
Feb 11, 2020
2
0
1
21
So I've installed PVE 6.1-7 on top of Debian 10 (Buster).
I used to run PVE 5 earlier that I had installed with the ISO and I did try that with the current version but unfortunately the installer didn't work for some reason.

So with the Debian installation comes the fact that the network bridge isn't automatically configured and I'm having difficulties with configuring and using it successfully.
The main difficulty understanding the bridges is the fact that the help documentation describes them acting like a switch, but the configuration page for one in the GUI includes an IP and gateway for the bridge (gateway can't be the same as the gateway for a physical interface??), which with my CCNA1 powers seems odd for an unmanaged switch (which I presume the bridge would be).

I've attached screenshots of the current bridge configuration (terminal) and network configuration for a container (GUI). The container can't get a network connection!

If there's some easy explanation for the bridges and how they're configured I'd love to read it, otherwise I'd just like to know how to make a bridge that works!
 

Attachments

Stoiko Ivanov

Proxmox Staff Member
Staff member
May 2, 2018
2,640
289
83
one in the GUI includes an IP and gateway for the bridge (gateway can't be the same as the gateway for a physical interface??), which with my CCNA1 powers seems odd for an unmanaged switch (which I presume the bridge would be).
a bridge behaves like a unmanaged switch in the sense that all ports you attach to the bridge are linked together and it forwards packets on Layer 2 (and learns the mac-addresses behind each port).
additionally you can configure an ip on that bridge (I think the rough equivalent on a cisco switch would be a loopback-ip - but am not too experienced with switches...)
keep in mind to configure the ip on the bridge and not on the physical interface you add to the bridge (to get the packets to go out of the host)

from the screenshot of your interfaces file i see that there is a mismatch:
* enp2s0f1 is the interface that gets it's link configured to up
* you add eno1 as bridge-port

check how the interface your want the packets to go out on is actually called - by running `ip link`
and add that as bridgeport

I hope that explains it
 
  • Like
Reactions: Tundral

Tundral

New Member
Feb 11, 2020
2
0
1
21
a bridge behaves like a unmanaged switch in the sense that all ports you attach to the bridge are linked together and it forwards packets on Layer 2 (and learns the mac-addresses behind each port).
additionally you can configure an ip on that bridge (I think the rough equivalent on a cisco switch would be a loopback-ip - but am not too experienced with switches...)
keep in mind to configure the ip on the bridge and not on the physical interface you add to the bridge (to get the packets to go out of the host)

from the screenshot of your interfaces file i see that there is a mismatch:
* enp2s0f1 is the interface that gets it's link configured to up
* you add eno1 as bridge-port

check how the interface your want the packets to go out on is actually called - by running `ip link`
and add that as bridgeport

I hope that explains it
Thanks a lot for the reply! So if I've interpreted correctly from looking at a valid config from a new install it seems that the physical port needs to not be active but not have any settings, instead it's set as a slave of the bridge and given an address. This way instead of the 'connection' being 'directly' bound to the Proxmox host it is instead bound to the switch (bridge) which can enable connectivity to the Proxmox host and the VMs?
 

Stoiko Ivanov

Proxmox Staff Member
Staff member
May 2, 2018
2,640
289
83
Thanks a lot for the reply! So if I've interpreted correctly from looking at a valid config from a new install it seems that the physical port needs to not be active but not have any settings, instead it's set as a slave of the bridge and given an address.
yes - the physical interface is left without any further configuration - it's just added to the bridge as port
all configuration happens on the bridge.
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE and Proxmox Mail Gateway. We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get your own in 60 seconds.

Buy now!