[SOLVED] single vlan not getting passed to guests

A

aaron2

New Member
Aug 13, 2024
3
0
1
As the title says.
I currently have 2 working network devices going to a VM (ID 101):
net0 on vmbr0, vlan 20 -- the main link, works fine
net1 on vmbr1 -- private link between VMs, works fine

My problem comes when I create the next link:
net2 on vmbr0, vlan 30 -- I can set the ip address (10.30.1.252/29) within the guest, and it can ping itself fine

On the Proxmox host, I have the two link devices connecting the guest to the bridge:
# ip link show up |grep vmbr0
45: fwpr101p0@fwln101i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP mode DEFAULT group default qlen 1000
69: fwpr101p2@fwln101i2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP mode DEFAULT group default qlen 1000

When I run a ping from the gateway (10.30.1.254), I can see the following on the Proxmox host:

# tcpdump host 10.30.1.252
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on enp3s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
11:29:34.761217 ARP, Request who-has 10.30.1.252 tell 10.30.1.254, length 42

I have several other VLANs (10,15,20,50) which are configured on the guests, these work fine. I'm certain that VLAN 30 is configured properly on the switch, as I can also see the following traffic on the Proxmox host's physical interface:

# tcpdump -n -e |grep "vlan 30"
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on enp3s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
12:30:20.288654 10:62:e5:13:2c:6b > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 60: vlan 30, p 0, ethertype ARP (0x0806), Request who-has 10.30.1.252 tell 10.30.1.254, length 42

So I can see the traffic hitting the host, but nothing seems to reach the VM. I've tried with the firewall disabled, and tried setting INPUT to accept by default. I've always had a default ping rule to allow either way.

As a test, I've just cloned a single guest, set it up with vlan30, and I'm seeing the same behaviour. So my theory that it breaks when I connect a 2nd link to vmbr0 on a single guest is blown.

I have a separate physical host on the same /29 subnet, on the same physical switch, which can communicate with the gateway and another IP on the /29 just fine.

I'm kinda stumped here, and not sure how to diagnose the issue further.

Any help would be fantastic!
 
Post your /etc/network/interfaces file from the Proxmox host.

What's the output of brctl show and bridge vlan show from the Proxmox host?
 
Last edited:
Thanks for replying.
I've noticed further behaviour - when the 3rd interface is created (net2), the first interface lost connectivity (net0). Once net2 is deleted, net0 started working again immediately.

Having extra eyes certainly helps. I see bridge-vids doesn't list the vlan in my interfaces config, even though my test vm still has vlan30 allocated. So the question then, is why wont it add?

root@bedrock:~# cat /etc/network/interfaces
Code: 
# network interface settings; autogenerated
# Please do NOT modify this file directly, unless you know what
# you're doing.
#
# If you want to manage parts of the network configuration manually,
# please utilize the 'source' or 'source-directory' directives to do
# so.
# PVE will preserve these directives, but will NOT read its network
# configuration from sourced files, so do not attempt to move any of
# the PVE managed interfaces into external files!

auto lo
iface lo inet loopback

auto enp3s0
iface enp3s0 inet manual

auto enx0000e8001ec0
iface enx0000e8001ec0 inet static
    address 10.10.1.230/24
    gateway 10.10.1.254
#MGMT Interface (USB)

auto vmbr0
iface vmbr0 inet manual
    bridge-ports enp3s0
    bridge-stp off
    bridge-fd 0
    bridge-vlan-aware yes
    bridge-vids 10,15,20,50
#VLAN Bridge for Guests

auto vmbr1
iface vmbr1 inet static
    address 192.168.1.1/24
    bridge-ports none
    bridge-stp off
    bridge-fd 0
#VM Private Network

root@bedrock:~# brctl show
Code: 
bridge name    bridge id        STP enabled    interfaces
fwbr100i0        8000.0639e5e3cd66    no        fwln100i0
                            tap100i0
fwbr101i0        8000.421caa1d2791    no        fwln101i0
                            tap101i0
fwbr102i0        8000.4ecd856be92c    no        fwln102i0
                            tap102i0
fwbr200i0        8000.86284541e0b2    no        fwln200i0
                            veth200i0
fwbr201i0        8000.e204583cf175    no        fwln201i0
                            veth201i0
fwbr202i0        8000.9e61bd416c80    no        fwln202i0
                            veth202i0
fwbr203i0        8000.1a5c56a872c8    no        fwln203i0
                            veth203i0
vmbr0        8000.408d5c780643    no        enp3s0
                            fwpr100p0
                            fwpr101p0
                            fwpr102p0
                            fwpr200p0
                            fwpr201p0
                            fwpr202p0
                            fwpr203p0
vmbr1        8000.9e6812ec06dd    no        tap101i1

root@bedrock:~# bridge vlan show
Code: 
port              vlan-id
enp3s0            1 PVID Egress Untagged
                  10
                  15
                  20
                  50
vmbr0             1 PVID Egress Untagged
vmbr1             1 PVID Egress Untagged
veth200i0         1 PVID Egress Untagged
fwbr200i0         1 PVID Egress Untagged
fwpr200p0         10 PVID Egress Untagged
fwln200i0         1 PVID Egress Untagged
veth201i0         1 PVID Egress Untagged
fwbr201i0         1 PVID Egress Untagged
fwpr201p0         20 PVID Egress Untagged
fwln201i0         1 PVID Egress Untagged
tap102i0          1 PVID Egress Untagged
fwbr102i0         1 PVID Egress Untagged
fwpr102p0         20 PVID Egress Untagged
fwln102i0         1 PVID Egress Untagged
tap100i0          1 PVID Egress Untagged
fwbr100i0         1 PVID Egress Untagged
fwpr100p0         20 PVID Egress Untagged
fwln100i0         1 PVID Egress Untagged
tap101i0          1 PVID Egress Untagged
fwbr101i0         1 PVID Egress Untagged
fwpr101p0         20 PVID Egress Untagged
fwln101i0         1 PVID Egress Untagged
tap101i1          1 PVID Egress Untagged
veth202i0         1 PVID Egress Untagged
fwbr202i0         1 PVID Egress Untagged
fwpr202p0         50 PVID Egress Untagged
fwln202i0         1 PVID Egress Untagged
veth203i0         1 PVID Egress Untagged
fwbr203i0         1 PVID Egress Untagged
fwpr203p0         30 PVID Egress Untagged
fwln203i0         1 PVID Egress Untagged

--------------------------------------------------------------------------------------

So I manually added vlan 30, added tested again but no dice. The new ouput:

root@bedrock:~# cat /etc/network/interfaces
Code: 
# network interface settings; autogenerated
# Please do NOT modify this file directly, unless you know what
# you're doing.
#
# If you want to manage parts of the network configuration manually,
# please utilize the 'source' or 'source-directory' directives to do
# so.
# PVE will preserve these directives, but will NOT read its network
# configuration from sourced files, so do not attempt to move any of
# the PVE managed interfaces into external files!

auto lo
iface lo inet loopback

auto enp3s0
iface enp3s0 inet manual

auto enx0000e8001ec0
iface enx0000e8001ec0 inet static
    address 10.10.1.230/24
    gateway 10.10.1.254
#MGMT Interface (USB)

auto vmbr0
iface vmbr0 inet manual
    bridge-ports enp3s0
    bridge-stp off
    bridge-fd 0
    bridge-vlan-aware yes
    bridge-vids 10,15,20,30,50
#VLAN Bridge for Guests

auto vmbr1
iface vmbr1 inet static
    address 192.168.1.1/24
    bridge-ports none
    bridge-stp off
    bridge-fd 0
#VM Private Network

root@bedrock:~# brctl show
Code: 
bridge name    bridge id        STP enabled    interfaces
fwbr100i0        8000.0639e5e3cd66    no        fwln100i0
                            tap100i0
fwbr101i0        8000.421caa1d2791    no        fwln101i0
                            tap101i0
fwbr102i0        8000.4ecd856be92c    no        fwln102i0
                            tap102i0
fwbr200i0        8000.86284541e0b2    no        fwln200i0
                            veth200i0
fwbr201i0        8000.e204583cf175    no        fwln201i0
                            veth201i0
fwbr202i0        8000.9e61bd416c80    no        fwln202i0
                            veth202i0
fwbr203i0        8000.1a5c56a872c8    no        fwln203i0
                            veth203i0
vmbr0        8000.408d5c780643    no        enp3s0
                            fwpr100p0
                            fwpr101p0
                            fwpr102p0
                            fwpr200p0
                            fwpr201p0
                            fwpr202p0
                            fwpr203p0
vmbr1        8000.9e6812ec06dd    no        tap101i1

root@bedrock:~# bridge vlan show
Code: 
port              vlan-id
enp3s0            1 PVID Egress Untagged
                  10
                  15
                  20
                  30
                  50
vmbr0             1 PVID Egress Untagged
vmbr1             1 PVID Egress Untagged
veth200i0         1 PVID Egress Untagged
fwbr200i0         1 PVID Egress Untagged
fwpr200p0         10 PVID Egress Untagged
fwln200i0         1 PVID Egress Untagged
veth201i0         1 PVID Egress Untagged
fwbr201i0         1 PVID Egress Untagged
fwpr201p0         20 PVID Egress Untagged
fwln201i0         1 PVID Egress Untagged
tap102i0          1 PVID Egress Untagged
fwbr102i0         1 PVID Egress Untagged
fwpr102p0         20 PVID Egress Untagged
fwln102i0         1 PVID Egress Untagged
tap100i0          1 PVID Egress Untagged
fwbr100i0         1 PVID Egress Untagged
fwpr100p0         20 PVID Egress Untagged
fwln100i0         1 PVID Egress Untagged
tap101i0          1 PVID Egress Untagged
fwbr101i0         1 PVID Egress Untagged
fwpr101p0         20 PVID Egress Untagged
fwln101i0         1 PVID Egress Untagged
tap101i1          1 PVID Egress Untagged
veth202i0         1 PVID Egress Untagged
fwbr202i0         1 PVID Egress Untagged
fwpr202p0         50 PVID Egress Untagged
fwln202i0         1 PVID Egress Untagged
veth203i0         1 PVID Egress Untagged
fwbr203i0         1 PVID Egress Untagged
fwpr203p0         30 PVID Egress Untagged
fwln203i0         1 PVID Egress Untagged
 
I added the net2 device on vlan30 back to vm101 today, and its working. So I'll mark as solved for now, and monitor.
 
You must log in or register to reply here.
Top Bottom