[SOLVED] No network access after install

proxmox_usr_2012

New Member
Jun 15, 2020
3
1
3
36
Edit: After posting this I did some more researching and came across this and the solution there solved my issue. For whatever reason the "ifupdown-pre" service is causing issues with the networking.service, and masking the "ifupdown-pre" service solved the issue. If the admins want to delete that's fine, but I was going to leave this post up in case anyone in the future needs it, and also to show that this seems to be a recurring thing with some users using Proxmox.

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

I've got a pfSense router which has several VLANs in my network, and I have the server directly attached to a Cisco switch with the network port configured as a VLAN access port. When I initially boot the server from the install USB, pfSense sees the server and assigns a DHCP IP address, but in the network section it doesn't pick up the DHCP lease of any of the network settings that you would normally get from the gateway. I had this server running Ubuntu prior to this install and all of the NICs worked fine and I had network connectivity, so I know my router and switch are set up correctly. There's something going on with the Proxmox network settings.

When I try to manually assign the server an IP address in the same subnet as the VLAN I cannot access anything on the network after install.

When I try to ping the gateway I get "Network is unreachable". When I type "ip a" at the terminal none of the interfaces show any ip address information, and the bridge doesn't show up either. It only shows the 4 NICs on the server. I also tried to change the /etc/network/interfaces to a DHCP config and reboot the server but same thing.

I don't have a way to access this server over the network, so I can't copy and paste the network information in here but I'll try to type as much of the relevant info as I can, and if you need more I can try to get it.

Prior to DHCP configuration the /etc/network/interfaces looked like this:

Code:
auto lo
iface eno1 inet loopback

iface eno1 inet manual

auto vmbr0
iface vmbr0 inet manual
    address 10.0.0.5/24
    gateway 10.0.0.1
    bridge_ports eno1
    bridge_stp off
    bridge_fd 0
 
iface eno2 inet manual
iface eno3 inet manual
iface eno4 inet manual

The DHCP config just has the address and gateway lines commented out, and changed "iface vmbr0 inet manual" to "iface vmbr0 inet dhcp"

The "ip a" output (condensed because I'm not going to manually type out everything):

Code:
1: lo: <LOOPBACK,UP,LOWER_UP>
          inet 127.0.0.1.....
2: eno1: <BROADCAST,MULTICAST> mtu 1500.....
         link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff:ff
3: eno2: <BROADCAST,MULTICAST> mtu 1500.....
         link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff:ff
4: (same as above, but eno3)
5: (same as above, but eno4)

"systemctl status networking.service" output showed that the networking service was loaded, but not active.

I used "systemctl start networking.service" and it started the networking service. When I then typed "ip a" the vmbr0 interface showed up with the same MAC as eno1, but no IP address was assigned still.

I went into the /etc/network/interfaces file and changed the configuration back to manual, and restarted the service but still no IP address and I still can't ping the gateway. I can't use ifup or ifdown because it isn't installed, and I obviously can't install it because I don't have network connectivity.

I used "systemctl enable networking.service" and rebooted the server. When I looked at "systemctl status networking.service" after reboot, it said "Dependency failed for Raise Network interfaces", and "networking.service: Job networking.service/start failed with result 'dependency'".

I went back into the /etc/network/interfaces and changed "iface vmbr0 inet manual" to "iface vmbr0 inet static" and restarted the networking service and it shows active and now "ip a" shows the static IP address for vmbr0, but now when I ping it no longer says "Network is unreachable", but now it just attempts to ping the gateway but says "Destination Host Unreachable".

So this is step in the right direction, but everytime I reboot the server it gives the dependency error, and I cannot seem to get networking up.

Anyone know what else I can do to troubleshoot this?
 
Last edited:

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, 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 yours easily in our online shop.

Buy now!