[SOLVED] VM and LXC not connecting to network on fresh install

DcVamps

New Member
Jan 6, 2023
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I am running into an odd issue. I have a relatively fresh install of Proxmox 7.3-4, and have an issue connecting to the network on almost any VM or LXC i create, with the exception of my Home Assistant OS VM, as that can for some reason connect to the network all the time. I am using a HP NC552SFP 10GB, dual port NIC, as I will eventually be adding a dedicated connection to my NAS for storage.

ip a:
Code:
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: enp131s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP group default qlen 1000
    link/ether 14:58:d0:b3:76:b8 brd ff:ff:ff:ff:ff:ff
3: enp131s0f1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 14:58:d0:b3:76:bc brd ff:ff:ff:ff:ff:ff
4: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 14:58:d0:b3:76:b8 brd ff:ff:ff:ff:ff:ff
    inet 192.168.XXX.XXX/24 scope global vmbr0
       valid_lft forever preferred_lft forever
    inet6 fe80::1658:d0ff:feb3:XXXX/64 scope link
       valid_lft forever preferred_lft forever
20: tap100i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr0 state UNKNOWN group default qlen 1000
    link/ether f2:f5:3b:ed:35:76 brd ff:ff:ff:ff:ff:ff
21: veth101i0@if2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP group default qlen 1000
    link/ether fe:cf:45:ae:b4:6f brd ff:ff:ff:ff:ff:ff link-netnsid 0

/etc/network/interfaces:
Code:
auto lo
iface lo inet loopback

auto enp131s0f0
iface enp131s0f0 inet manual

iface enp131s0f1 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.XXX.XXX/24
        gateway 192.168.XXX.XXX
        bridge-ports enp131s0f0
        bridge-stp off
        bridge-fd 0
I have a Mikrotik router, that currently is only managing static IP leases, and some lightweight firewall rules for reverse proxy, and port forwarding for a couple other services, and the main host is able to ping, and has network access.

Example of the issue I am seeing attached, using the docker LXC script bash -c "$(wget -qLO - https://github.com/tteck/Proxmox/raw/main/ct/docker-v5.sh)" from https://tteck.github.io/Proxmox/
 

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What happens if you select "continue anyway"?
When I select continue anyways, the LXC creates, and I get a warning to expect issues without internet, a DNS lookup failure, and an error installing dependencies.

When I attempt to access https://8.8.8.8:443 in a browser on a brand new VM using Linux Mint 21, and Ubuntu desktop 22.04, i get the following issue
Code:
Unable to connect

An error occurred during a connection to 8.8.8.8.

The site could be temporally unavailable or too busy. Try again in a few moments.
If you are unable to load any pages, check your computer's network connection
If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the web


FWIW, You'll get faster responses if you report issues in the repo
This one just an example. even when creating VMs from scratch, I am having the same issue, other than Home Assistant OS for some reason.
 
Can the proxmox host ping 8.8.8.8? If you run apt update at the proxmox host cli what happens?
 
OK, it's been a minute, since I was dealing with COVID.

After testing the Routed Configuration, and the NAT and iptables, and neither worked, I decided to see if the minimal portforwarding and hairpin NAT i needed for SWAG reverse proxy was causing issues. That was also not the issue either. I even attempted to see if i could recreate this issue in a different OS, so I tried unRAID, This was still happening on unRAID as well.

Turns out, the 10GB NIC I am using is not compatible with either Proxmox or unRAID.

(edit)
The new 10GB NIC I obtained (intel 82599EN) is indeed compatible, and is working just fine, even in the default bridge mode. The HP NC552SFP I was originally using was indeed the only issue with my installation.
 
Last edited:
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