Graphical console does not work - HELP PLEASE

Hi, I have been using Cloudmin (KVM) on an Ubuntu server for over 2 years and suddenly I started to have problemes on new virtual machines and selected old VMs when trying to open the graphical console.

This is the message I get: VNC has been configured on this system by Cloudmin, but the VNC server on port 590x on host system server.aaa.bb is not accessible. If it was just enabled, the system will need to be rebooted before VNC is available. No password provided so I cannot VNC with other clients.

Tried to upgrade, reboot VM and host, rebuild VMs at no avail. What can it be? Hereunder details of the host system Thank you Massimo

System hostname server.aaa.bb (10.10.x.x) Operating system Ubuntu Linux 12.04.5 Webmin version 1.770 Cloudmin version 8.3.kvm Time on system Thu Oct 15 19:50:57 2015 Kernel and CPU Linux 3.2.0-91-generic on x86_64 Processor information AMD FX(tm)-8350 Eight-Core Processor , 8 cores
System uptime 3 days, 23 hours, 54 minutes Running processes 198
CPU load averages 3.26 (1 min) 3.26 (5 mins) 3.35 (15 mins)

Status: 
Closed (fixed)

Comments

Do you perhaps have a firewall on your system that is blocking access to the VNC port mentioned in the error message?

Hi, thanks for your reply but I can confirm this is not the case. In fact, as said, I can still access VMs create long time ago.

I also noted the following message appearing when I start the problematic VMs: " Starting up vm1 .... .. failed : KVM instance was started OK, but the graphical console password could not be set : Monitor command timed out after 10 seconds "

Max

Interesting - that suggests that the VM didn't properly start at all.

Can you access the VM via SSH, or even ping it?

Dear Jamie, yes I think captioned systems do not actually start up.

The only unusual thing I did was to change the Host System IP and subnet, from 192.168.101.xxx to 10.10.x.x due to a major reconfiguration of my LAN.

Can this be the cause? Is there anything I can do to fix? As it is, the system is totally unusable, as I cannot create new systems any more.

Last resort, I can rebuild Host System from scratch, but it is not my preferred option.

Max

That could be the cause. Did you also change the IP addresses of your VMs to be on the same subnet?

Well, my VMs are on various different subnets, lan1, lan2, DMZ according to the task they perform I changed their IP either manually or through DHCP.

Should I change also something inside Cloudmin?

Thinking again about the issue, it sounds strange to me that the VMs IP can impede VMs to start or affect VNC,

As a matter of fact, graphical console should always works, also on VMs when their NIC is missing, disabled or not yet initialized.

Do you think it possible that Cloudmin tries to connect to host using the former IP instead of using localhost or resolving hostname through /etc/hosts?

It's possible that Cloudmin is attempting to connect to the host system using the wrong IP.

Make sure that in DNS and in the /etc/hosts file on the Cloudmin master and the VM host that the new IP address for the hostname is set correctly.

Double checked and everything looks ok. This is becoming a real mistery. Over the week-end I plan to rebuild the host system. I need to restart all VMs and create new ones. Thanks

Double checked and everything looks ok. This is becoming a real mistery. Over the week-end I plan to rebuild the host system. I need to restart all VMs and create new ones. Thanks

If possible, I could login to your Cloudmin master system and take a look to see what's going wrong. You can email me login details at jcameron@virtualmin.com

Thank you very much Jamie for finding out that there was a problem with the spelling of localhost in /etc/hosts and solving the issue. Strange enough only new VMs were affected and all the rest was working fine. This error must have been present since the host was originally installed.

Great job!

Max

Glad we got that sorted out. I will update Cloudmin in the next release to use the IP 127.0.0.1 instead of localhost, to defend against this kind of mis-configuration.