PMX 7.2-7: no network after creating a 2nd bridge (clean instance)

[Zamana]

Hello!

We just installed a new instance of Proxmox (7.2-7) in a server with 4 NICs, and it is completely clean. No CTs, VMs, whatever.

Everything is fine, except that every time we tried to create a 2nd bridge to the another eno* NIC, through the web interface, we lost network access to the server (everything: web ui, ssh, ping etc).

The only way to recover is to access the console and reset the network configuration to the default:



/var/log/messages is attached for reference.

So, is there a way to troubleshoot this issue?

Thank you.
Best regards.

 

[shrdlicka]

Hi,
what does the configuration look like of the second bridge when you set it up?

 

[Zamana]

Hi!

Thanks for replying.

I can't apply the configuration right now, but I guess this would help:

--- /etc/network/interfaces    2022-07-14 14:50:38.538572632 -0300
+++ /etc/network/interfaces.new    2022-07-15 17:44:22.785621860 -0300
@@ -27,3 +27,11 @@
     bridge-ports eno1
     bridge-stp off
     bridge-fd 0
+
+auto vmbr1
+iface vmbr1 inet static
+    address 10.100.50.70/16
+    bridge-ports eno2
+    bridge-stp off
+    bridge-fd 0
+

The current/initial configuration that is working right now, is like this:

auto lo
iface lo inet loopback

iface eno1 inet manual

iface eno2 inet manual

iface eno3 inet manual

iface eno4 inet manual

auto vmbr0
iface vmbr0 inet static
        address 10.99.99.25/24
        gateway 10.99.99.1
        bridge-ports eno1
        bridge-stp off
        bridge-fd 0

 

[bobmc]

Are the ports bonded on the switch?

 

[Zamana]

If by "bonded" you mean "if there is a network cable connecting the NIC and the switch", yes. All of them are connected.

 

[bobmc]

No, I mean paired together for redundancy and/or bandwidth optimisation - aka link aggregation

 

[Zamana]

Got it.

No. All the NICs are isolated, independent.

 

[shrdlicka]

if you are trying to set it up again and it fails, can you check the output of ip a to see if the interfaces are still UP.

 

[Zamana]

Hi!

We applied the configuration right now, and lost the network again. Here is the output of "ip a" obtained from console after the bridge was created:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP group default qlen 1000
    link/ether d0:94:66:2e:d0:8c brd ff:ff:ff:ff:ff:ff
    altname enp2s0f0
3: eno2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr1 state UP group default qlen 1000
    link/ether d0:94:66:2e:d0:8d brd ff:ff:ff:ff:ff:ff
    altname enp2s0f1
4: eno3: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether d0:94:66:2e:d0:8e brd ff:ff:ff:ff:ff:ff
    altname enp3s0f0
5: eno4: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether d0:94:66:2e:d0:8f brd ff:ff:ff:ff:ff:ff
    altname enp3s0f1
20: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether d0:94:66:2e:d0:8c brd ff:ff:ff:ff:ff:ff
    inet 10.99.99.25/24 scope global vmbr0
       valid_lft forever preferred_lft forever
    inet6 fe80::d294:66ff:fe2e:d08c/64 scope link
       valid_lft forever preferred_lft forever
21: vmbr1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether d0:94:66:2e:d0:8d brd ff:ff:ff:ff:ff:ff
    inet 10.100.50.70/16 scope global vmbr1
       valid_lft forever preferred_lft forever
    inet6 fe80::d294:66ff:fe2e:d08d/64 scope link
       valid_lft forever preferred_lft forever

 

[shrdlicka]

Can you check if the port is open via telnet from both IP subnets

telnet IP 8006

What does your /etc/hosts look like. Can your IP from /etc/network/interfaces also be found in the hosts file?

 

[Zamana]

After the 2nd bridge, this is the status of:

/etc/hosts:

127.0.0.1 localhost.localdomain localhost
10.99.99.25 pmx.xxxx.corp pmx

# The following lines are desirable for IPv6 capable hosts

::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts

And here is the status of:
netstat -an | grep -iw listen:

tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:85            0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN
tcp6       0      0 :::8006                 :::*                    LISTEN
tcp6       0      0 ::1:25                  :::*                    LISTEN
tcp6       0      0 :::3128                 :::*                    LISTEN
tcp6       0      0 :::22                   :::*                    LISTEN
tcp6       0      0 :::111                  :::*                    LISTEN

But telnet 10.99.99.25 8006 does not work:

telnet 10.99.99.25 8006
Trying 10.99.99.25...
telnet: Unable to connect to remote host: Resource temporarily unavailable

 

[Zamana]

Any idea what could be wrong?

 

[shrdlicka]

You could try restarting the pveproxy service:

systemctl restart pveproxy.service