Bug - PVE Cluster: VNC error on node

Pavel Olenev

New Member
May 10, 2012
8
1
3
Hi!


I have some problem when using vnc console on Proxmox VE 2.1. My cluster contains four proxmox ve servers. When I trying to open vnc console from GUI on master server to virtual machine on node (10.0.0.30) I get this error:

TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/bin/ssh -T -o BatchMode=yes -c blowfish-cbc 10.0.0.30 /usr/sbin/qm vncproxy 133 2>/dev/null'' failed: exit code 255


This error I get with any vm on current node. All other node work fine.
If I open GUI from this node (10.0.0.30) - vnc console work fine too.
 
I think that I have the same issue, ... the message that I am getting is:

TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/sbin/qm vncproxy 100 2>/dev/null'' failed: exit code 1

I think there needs to be a VNC server installed and configured to support that connection, ... or if that is already in place maybe a firewall rule is preventing it ... any ideas anyone?
 
I think that I have the same issue, ... the message that I am getting is:

TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/sbin/qm vncproxy 100 2>/dev/null'' failed: exit code 1

I think there needs to be a VNC server installed and configured to support that connection, ... or if that is already in place maybe a firewall rule is preventing it ... any ideas anyone?

I am also seeing this exact same error when trying to access the console from the GUI. I know this worked the last time I used it which was a few days ago. I know my java was just updated on my PC. I wonder if that has anything to do with it.
 
@adamb: If you are running Windows (XP), the Java update should have kept you previous version, and you can revert back to it, can you please check and let me know which version it was?
I think I have Java(TM) 6 Update 31 on mine, right now where I am getting the error.
 
Yes, this could be the solution, that's also written in the link I posted and it solved the problem for me. But Pavel has "exit code 255", don't know if this matters!


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OK, I got it to work, too, with Firefox 12 and Java (TM) 6 update 31, I guess I was trying this with Chrome, and that one seems to be the reason for the errors.
 
I have this problem only on one current node on cluster. I.e node 1 is master. If I open GUI from node 1 - I can access VNC to vm on nodes 1,2,4,5,6 etc. But have error on node 3 only. If I open gui from node 3 - I can access to vnc console on this node. All nodes is updated. I think if problem was in firefox/chrome/java - it will be problem with all nodes, not only with current one. And in our network this problem in all computers, not only mine.
 
I had the same issue as stated above, updated the java with the latest Firefox and that resolved the issue, I did however have to reload the console session to see the changes.
 
Sorry to resurrect an old thread but no solution was yet posted for the OP's problem that I too am having exactly. Error code 255 is the key.

I have this problem only on one current node on cluster. I.e node 1 is master. If I open GUI from node 1 - I can access VNC to vm on nodes 1,2,4,5,6 etc. But have error on node 3 only. If I open gui from node 3 - I can access to vnc console on this node. All nodes is updated. I think if problem was in firefox/chrome/java - it will be problem with all nodes, not only with current one. And in our network this problem in all computers, not only mine.

I'm having this exact problem as well, exit code 255 (which is different from exit code 1 which is usually a timeout.)
Code:
TASK  ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/bin/ssh -T -o  BatchMode=yes <ip.of.node.3> /usr/sbin/qm vncproxy 131 2>/dev/null''  failed: exit code 255

For clarification: I'm connected to the GUI on node1. I can start consoles of VMs on node1 and node2 but I get the above error when trying to do so on node3. The only interesting things I can think of are that node3 was recently installed and the last node added to the cluster. The console I'm trying to access is of a VM that was just recently created.

Thank you for any help. I wish there was a log somewhere that showed what exactly that exit code means or what happened.
 
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And replying to my own problem, apparently you must manually SSH as root once from the machine whose Web GUI you're accessing to every other cluster node to add the keys to the known_hosts file. Even though I had done this for node3 from node1 already, I hadn't done it for node2 from node1 which made the difference. Don't ask me why!

(I found this out by copying the command from the error message to a root prompt on node1 (the Web GUI.) I ran it, then manually tried to connect using vncviewer to port 5900 in this case. It was at that point that I saw 'Host key verification failed.' which was the clue I needed. Apparently error 255 means 'Host key verification failed.' in this instance?)
 
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Hello guys,

i m a new user of PROXMOX and presently when i want to connect my vm using console i am getting a error
TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/sbin/qm vncproxy 100 2>/dev/null'' failed: exit code 1
i am already update my java version and mozilla and chrome can anyone help me to out of this problem. I m waiting for your reply.
 
Help Me Please,,,, i have problem with proxmox
When i remote node via console no vnc and vnc..
TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/sbin/qm vncproxy 100 2>/dev/null'' failed: exit code 255
 
Hi all, I had the same problem:
"TASK ERROR: command '/bin/nc -l -p 5900 -w 10 -c '/usr/sbin/qm vncproxy 100 2>/dev/null'' failed: exit code 255".
I resolved it by check ssh connection bettwen nodes on cluster and restart pvedaemon.
 
For some reason this just started happening to me as well since a few days ago. I didn't update Proxmox at all, so I can't imagine it's a proxmox issue.

Code:
TASK ERROR: command '/bin/nc6 -l -p 5900 -w 10 -e '/usr/bin/ssh -T -o BatchMode=yes <ip address> /usr/sbin/qm vncproxy 303 2>/dev/null'' failed: exit code 1
 

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