Web UI and ssh not answering soon after start

[k081xoes]

Try using 10.10.1.65 as an IP address, usually using the first / last IP address of a range is not a good idea.

Should I reinstall Proxmox or I can do it using console or web ui?

 

[shanreich]

Should I reinstall Proxmox or I can do it using console or web ui?

You should just be able to set it when you click on the Host > System > Network in the Web UI

edit: you will also have to update your /etc/hosts file, so it contains the new IP

 

[k081xoes]

You should just be able to set it when you click on the Host > System > Network in the Web UI

edit: you will also have to update your /etc/hosts file, so it contains the new IP

I've change IP to 65 in "Network in the Web UI" (interface vbr0), in /etc/host and in router.
I've connected after reboot, but, in several minutes connections were broken with same symptoms.

 

[richard.f.m]

I have the same problem since today

 

[k081xoes]

Hi,
can you exclude a RAM issue? Try running a memory test.. Also, can you login to the machine physically when the ssh connection and WebUI fail? If yes, can you check disk usage, memory usage, dmesg -w, journal...

Dear Chris, I finally can log in to machine when it breaks connection.
What should I check?

UPD: As I see, both ssh and pveproxy are working and ok (although, they are unavailable from my local machine). There are no errors or termination signals.

 

[Chris]

What should I check?

Running out of ideas here.. since you have nothing in the logs.. You could run arp -a to check the mac addresses or check with tools such as socat if your network remains up while services such as sshd and pveproxy loose connection.

 

[Neobin]

I only skimmed over the thread, but:

I've registered IP at the side of router.

I would remove this completely and try with a simple default network configuration with a static IP only set on the PVE-host: [1].

The following outputs in code-tags from the current configuration might also be helpful:

• cat /etc/network/interfaces
• cat /etc/hosts
• ip a

[1] https://pve.proxmox.com/wiki/Network_Configuration#_default_configuration_using_a_bridge

 

[k081xoes]

I only skimmed over the thread, but:

I would remove this completely and try with a simple default network configuration with a static IP only set on the PVE-host: [1].

The following outputs in code-tags from the current configuration might also be helpful:

• cat /etc/network/interfaces
• cat /etc/hosts
• ip a

[1] https://pve.proxmox.com/wiki/Network_Configuration#_default_configuration_using_a_bridge

Dear Neobin,
output is attached.
I've disabled static ip before getting it.

 

[k081xoes]

I have a hypothesis.
I've set ip and subnet as 10.10.1.65/27. And gateway ip is 10.10.1.1.
I suppose that it could cause some conflict (gateway is out of subnet) and it was a reason of such a strange behaviour.
As for now, I have change subnet to /24. Already 10 minutes it works. I'll try to keep it for some hours to check, whether the problem is solved.

UPD: 40 minutes up. It seems working fine.

UPD2: Problem is solved. Great thanks for your help!

 

[z99]

Same, i also have similar problem. Server up, and sometimes suddenly cannot access webmail and SSH. Ping still works

 

[wLoooo]

I have a similar problem.

Reading the thread pointing at the network gateways I noticed I started having problems roughly at the time after I added a Linux bridge with:

• a specific lan tag
• not assigned to a specific port hardware port
• a different network than the UI
• It had a gateway defined outside of the subnet for the UI.

I removed this now and I hope that this solves the issue.

Update: after 18h it is still working.

 

[anusuya]

ubuntu@test:~/.ssh$ ssh -vvv -i id_ed25519 ubuntu@192.168.1.80
debug1: OpenSSH_10.0p2 Debian-7, OpenSSL 3.5.1 1 Jul 2025
debug3: Running on Linux 6.14.8-2-pve #1 SMP PREEMPT_DYNAMIC PMX 6.14.8-2 (2025-07-22T10:04Z) x86_64
debug3: Started with: ssh -vvv -i id_ed25519 ubuntu@192.168.1.80
debug1: Reading configuration data /etc/ssh/ssh_config
debug3: /etc/ssh/ssh_config line 19: Including file /etc/ssh/ssh_config.d/20-systemd-ssh-proxy.conf depth 0
debug1: Reading configuration data /etc/ssh/ssh_config.d/20-systemd-ssh-proxy.conf
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug2: resolve_canonicalize: hostname 192.168.1.80 is address
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts' -> '/home/bsetec/.ssh/known_hosts'
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts2' -> '/home/bsetec/.ssh/known_hosts2'
debug3: channel_clear_timeouts: clearing
debug3: ssh_connect_direct: entering
debug1: Connecting to 192.168.1.80 [192.168.1.80] port 22.
debug3: set_sock_tos: set socket 3 IP_TOS 0x10
debug1: Connection established.
debug1: identity file id_ed25519 type 3
debug1: identity file id_ed25519-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_10.0p2 Debian-7
kex_exchange_identification: read: Connection reset by peer
Connection reset by 192.168.1.80 port 22 - any idea about this issue?