Cluster and quorum....

diaolin

Member
Jul 7, 2008
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Trentino Italy
Hi, i have two machines correctly seen when they are up and running but, when i start only one of the two and i probe creating a new VM i have an error:

Boot: Starting cluster OK
Starting cman OK
all oK until quorum that obviously says:

Waiting for quorum... timed out...
[FAILED]
Cluster not ready - no quorum?


when i try to create a new KVM machine the interface says

cluster not ready - no quorum? (500)

Why?
It's unpossible creating a new machine without cluster?

I-ve found that /etc/pve is readonly...

Tx, Diaolin
 
Last edited:

tom

Proxmox Staff Member
Staff member
Aug 29, 2006
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without quorum you cannot do anything, that´t the concept and the expected behavior. do you have a two node setup? do you use a qdisk?
 

tom

Proxmox Staff Member
Staff member
Aug 29, 2006
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it seems that you do not understand the basic nature of a cluster and a quorum. and you did not answer my questions. do you have a quorum disk?

if a two node cluster is divided, each node have just one vote. its a "democratic" system, so with a two node cluster you end in unresolved situation. each node have one vote and no node have a majority of votes (1:1)

so either use at least 3 nodes or took the right measures for a 2 node system (e.g. configure a quorum disk)
 

diaolin

Member
Jul 7, 2008
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Trentino Italy
Ah, ok
now i undestand my trouble.
I don't have a quorum disk. But, do you think that is possible to have a quorum disk with two nodes without a dedicated separate storage?
Tx
 

dietmar

Proxmox Staff Member
Staff member
Apr 28, 2005
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www.proxmox.com
Ah, ok
now i undestand my trouble.
I don't have a quorum disk. But, do you think that is possible to have a quorum disk with two nodes without a dedicated separate storage?
No, a quorum disk needs some sort of shared storage.

Note: It is also possible to assign 2 votes to one node.
 

OO-Dragon

New Member
Jan 10, 2010
16
0
1
Go on...? .. How does one do that?
I seemed to have figured out how.

on both servers, run

Code:
/etc/init.d/pve-cluster stop
then

Code:
/usr/bin/pmxcfs -l
then edit both configs on both machines to change votes

Code:
nano /etc/pve/cluster.conf
You'll see your 2 servers, just edit the same one on both servers to have a vote of 2 and the other leave as 1. Save the configs and reboot the systems. Should be fine and dandy.
 

OO-Dragon

New Member
Jan 10, 2010
16
0
1
If you want to force quorum, you can simply set the expected votes to 1:

# pvecm expected 1
I tried that originally but it wouldn't connect because cman wouldn't stay running due to quorum timing out. Or do you mean just run with local pmxcfs then do that command?
 

MikeP

Member
Feb 14, 2016
47
4
8
49
If you want to force quorum, you can simply set the expected votes to 1:

# pvecm expected 1
For a test cluster, I have 2 nodes. One of them is offline. So, following this, I checked

#pvecm status
### this showed that expected was 2 for 2 nodes.
#pvecm expected 1
#pvecm status
### this now shows expected as 1.
### this lets me run with only 1 of the 2 working. This is not recommended for production nor HA, but is great for my home lab with two boxes, so I don't need to power them both on all the time.
 

netdesignate

New Member
Apr 18, 2013
7
0
1
Jacksonville, FL
For a test cluster, I have 2 nodes. One of them is offline. So, following this, I checked
### this lets me run with only 1 of the 2 working.
This is not recommended for production nor HA, but is great for my home lab with two boxes, so I don't need to power them both on all the time.
This was a very useful post for me - THANKS MikeP
 

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