Proxmox reinstall and restore

Maher Khalil

Member
Jul 11, 2021
129
5
18
41
Hello
after I reboot proxmox 7, I cannot access GUI or ssh while some VPSs work and some other does not work
what should I do
 

Dunuin

Famous Member
Jun 30, 2020
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Germany
First I would attach a keyboard+display or use webKVM to access the console to see whats going on. Then I would check the network configuration, check the syslog and check if the sshd and pveproxy services are running.
 

Maher Khalil

Member
Jul 11, 2021
129
5
18
41
what I found after ssh the system using KVM is that proxmox cannot ping google.com
I think that is dns problem right?
 

Maher Khalil

Member
Jul 11, 2021
129
5
18
41
What I found is that I cannot ping my server IP nor ping google.comf from inside my server. firewall is disabled using KVM, so I expect it is a router problem
 

Tmanok

Active Member
What I found is that I cannot ping my server IP nor ping google.comf from inside my server. firewall is disabled using KVM, so I expect it is a router problem
It could also be misconfigured NIC on the server itself. Can anything reach the server? Your title says that you restored the system, did you restore /etc/network/interfaces too?
Cheers,

Tmanok
 

Maher Khalil

Member
Jul 11, 2021
129
5
18
41
Hello
It is now working
my setting of the interfaces which makes the problem
==================================================================>
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 <subnet IP>
gateway <subnet gateway>
bridge-ports eno1
bridge-stp off
bridge-fd 0

=====================================================================>
My setting which solves the problems is
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 <main server IP>
gateway <main server gateway>
bridge-ports eno1
bridge-stp off
bridge-fd 0
===========================================================================>

Now subnet is not mentioned on interfaces and server + VM with subnet IPs working perfectly
Any advice
 

Tmanok

Active Member
Hi Maher,

It is a little bit ambiguous what you've done so I'll reveal a sample config and then offer a path forward for you.

iface eno1 inet manual

auto vmbr0
iface vmbr0 inet static
address 192.168.0.2/24
gateway 192.168.0.1
bridge-ports eno1
bridge-stp off
bridge-fd 0

What I've done there should be similar to your config with the addition of the subnet (/24) to the address. Your addresses may be different (e.g. 10.0.0.x 172.16.0.x or other derivatives), find out what the appropriate subnet mask is, for example 255.255.255.0 is /24 but the subnet can be anything from (255.0.0.0) /8 to (255.255.255.252) /30 really.

My advice is that if you can reach the web GUI, consider updating network settings there instead as they will be formatted appropriately for you. :)

Thanks, let me know if there is still an issue and explain your objective (e.g. "I want to reach x network or device").


Tmanok
 
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Maher Khalil

Member
Jul 11, 2021
129
5
18
41
Hello
I have done same as per your example with replacing 192.168.0.2/24 to my subnet IP/CIDR and gateway (same as before problem occurs) but when do this I cannot access GUI
 

Tmanok

Active Member
Hello
I have done same as per your example with replacing 192.168.0.2/24 to my subnet IP/CIDR and gateway (same as before problem occurs) but when do this I cannot access GUI
Ok, simple troubleshooting first:
  1. Is the PVE node able to ping anything else on the network? -> If no, check cabling and configuration.
  2. Is the PVE node able to ping the router? -> If no, continue:
  3. Are other physical hosts able to ping PVE? Consider trying multiple.
  4. Are other physical hosts on the network able to ping the router? If not, then it's likely another issue outside of PVE.
Assuming the answer to #4 is yes, we should proceed to assume that the issue could be the PVE configuration.
A simple measure to ensure that your interface is appropriately configured is to run ip a

Look for: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP group default qlen 1000
The important parts are "state UP" and "master vmbr0". If these are not visible in the line, then the configuration is incorrect / possible syntax error. If they are both present, then there could be incorrect network address, subnet, or router configured. Lastly, again please check hardware.

If nothing seems to help, see if there is a DHCP server on the network and you can change:
Code:
auto vmbr0
iface vmbr0 inet static
address 192.168.0.2/24
gateway 192.168.0.1
bridge-ports eno1
bridge-stp off
bridge-fd 0

To:
Code:
auto vmbr0
iface vmbr0 inet dhcp
#address 192.168.0.2/24
#gateway 192.168.0.1
#bridge-ports eno1
#bridge-stp off
#bridge-fd 0

Cheers, best of luck with the issue.

Tmanok
 
Last edited:

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