Cant connect to host gui or ssh

[memilanuk]

Well... nuts. Misery loves company.

My Proxmox host was up and running last night at midnight, just fine. Finished setting up a new VM (Ubuntu 20.04 LTS server) and mounting an external drive in it that I had passed thru from the host, and went to bed.

Got up this morning... no proxmox web ui. Can't ssh into the host. But I can ssh into the new VM that I left running. The VM seems just fine. But no response from the host... which is of course, headless

 

[pharpe]

Well... nuts. Misery loves company.

My Proxmox host was up and running last night at midnight, just fine. Finished setting up a new VM (Ubuntu 20.04 LTS server) and mounting an external drive in it that I had passed thru from the host, and went to bed.

Got up this morning... no proxmox web ui. Can't ssh into the host. But I can ssh into the new VM that I left running. The VM seems just fine. But no response from the host... which is of course, headless

Yeah it appears to be an undocumented feature. What version are you running? I'm considering upgrading to see if the issue is resolved in v6.

 

[memilanuk]

Yeah it appears to be an undocumented feature. What version are you running? I'm considering upgrading to see if the issue is resolved in v6.

6.3-4, here.

Something weird happened where the physical network interface picked up the same IP address as the bridged virtual interface from DHCP. I think in my case it had something to do with running Ubiquiti Unifi on the local LAN, and 'fixed' addresses (aka DHCP reservations). I had to disable DHCP, flush a few things in the UniFi controller (and via ssh on the USG), reboot the proxmox box and suddenly everything worked again

 

[pharpe]

6.3-4, here.

Something weird happened where the physical network interface picked up the same IP address as the bridged virtual interface from DHCP. I think in my case it had something to do with running Ubiquiti Unifi on the local LAN, and 'fixed' addresses (aka DHCP reservations). I had to disable DHCP, flush a few things in the UniFi controller (and via ssh on the USG), reboot the proxmox box and suddenly everything worked again

Thanks. I also have a Unifi controller running. I shut that down and rebooted proxmox but no change.

I shut down the DHCP server on my router and rebooted proxmox. Since there was no DHCP server it could get an IP lease and started working. Obviously not having a DHCP server isn't a long term solution however. I guess I could try to setup some kind of firewall rule that blocks proxmox from the DNS ports so it can't get an IP lease but that seems like more of a hack than a fix.

 

[2707974]

Thanks. I also have a Unifi controller running. I shut that down and rebooted proxmox but no change.

I shut down the DHCP server on my router and rebooted proxmox. Since there was no DHCP server it could get an IP lease and started working. Obviously not having a DHCP server isn't a long term solution however. I guess I could try to setup some kind of firewall rule that blocks proxmox from the DNS ports so it can't get an IP lease but that seems like more of a hack than a fix.

Like I write, now with DHCP server turned off, check config /etc/network/interface

This config should be proper for you PVE host

auto lo
iface lo inet loopback

iface enp3s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.74/24
        gateway 192.168.1.1
        bridge-ports enp3s0
        bridge-stp off
        bridge-fd 0

static in configuration should prevent from dynamic aka DHCP config of interface

If you don't get ip on interface after restart do

systemctl restart networking

If stiil don't get ip, with command

ip a

or

ip link

check names of you network adapters and based on output change name

 

[pharpe]

Like I write, now with DHCP server turned off, check config /etc/network/interface

This config should be proper for you PVE host

auto lo
iface lo inet loopback

iface enp3s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.74/24
        gateway 192.168.1.1
        bridge-ports enp3s0
        bridge-stp off
        bridge-fd 0

static in configuration should prevent from dynamic aka DHCP config of interface

If you don't get ip on interface after restart do

systemctl restart networking

If stiil don't get ip, with command

ip a

or

ip link

check names of you network adapters and based on output change name

The issues is that I am getting an IP that I don't want not the other way around. This is how my /etc/network/interface is set. The problem is that it's ignoring the config for enp3s0 and assigning it an IP lease from DHCP. No matter what I put in the /etc/network/interface for enp3s0 (static or manual) it gets ignored and assigned a DHCP IP address. I was able to setup a DNSMASQ rule in my router/DHCP server to not assign a IP to the MAC address of the Promox host. It's now working so I was able to fix it externally but something is still wrong on the server.

 

[CryptoVibe]

I had this happen to me also. I had checked the "Firewall" button here & it would not let me SSH in. As soon as I unchecked it, I am able to SSH back in:

 

[remark]

I had this happen to me also. I had checked the "Firewall" button here & it would not let me SSH in. As soon as I unchecked it, I am able to SSH back in:

View attachment 49499

Create accepting incoming rule for SSH.