Operating System - OpenVMS
1748170 Members
4332 Online
108758 Solutions
New Discussion юеВ

Re: OpenVMS cluster print queue setup

 
SOLVED
Go to solution
M C_1
Advisor

OpenVMS cluster print queue setup

OK - I know this is not a very popular topic but I have some questions about Cluster Print Queue Setup..

I have a two node cluster running VMS 7.2-2 with one system disk. No LPD no DQS just plain terminal printing via LAT and Multinet. There is only one queue manager.

System1 runs the queue manager

Both system1 and system2 have queues defined in their startup. The queue manager running on System1 is set to failover onto System2 in the event System1 goes down.

I would like to set all my queues to autostart failover to the opposite system they are defined on. I know that I would have to re-init each queue with /autostart_on=(system1::,system2::) and then in my startup start/queue on each queue and then $enable autostart/queue on system1 and system2.

However, my question is two-fold:

1) If system1 crashes, the queue manager will move to run on system2, however, will the autostart queues defined on system1 automatically move over to system2? The VMS documentation says on a system shutdown a $ disable autostart/queue is issued to move the queues over to the existing node if they are defined for failover. However, there is no mention of on a Crash...

2) If indeed the queues do move over on a shutdown and/or a crash, once system1 is back up and stable, how do you move the queues that failed over back to the original system?

3) Also, if system1 crashed and the queue manager moved to system2, when system1 comes back on-line will it attempt to start the queue manager? What about system2?

Sorry for the long note... Thanks so much for your feedback..

MC
It is what it is!
16 REPLIES 16
David Harrold
Advisor

Re: OpenVMS cluster print queue setup

Hi MC,

I can't answer quesiton 1 about the queue failover. I think they do, but it has been so long since I tested that, I don't remember.

About failing queues back, no they don't move back to SYSTEM01 when the startup performs the ENABLE AUTOSTART/QUEUE. The way I move them is a stop/queue/reset followed by a start/queue .

for the third question, it depends. How do you do the start up of the queue manager in you SYSTARTUP_VMS.COM? If you do something like START/QUEUE/MANAGER/ON=(SYSTEM1,SYSTEM2,*), then it should move it back to SYSTEM1 when it boots. Otherwise I believe it stays where it is.

Hope that helps.

Dave Harrold
Jan van den Ende
Honored Contributor

Re: OpenVMS cluster print queue setup

Hello MC.

The answer to 1):
IF you have set up your queues to be allowed to run on both (all) systems, they DO failover correctly.
(Only jobs-in-progress might fail, depending on what is already in the printers' buffer and what still needs sending. If you set up your queue /RETAIN=ERROR you will recognise those immediately, and you can re-issue them.) Jobs pending are not affected.

If you set up your queues to be /ON=(node1,node2,...), then after STOP/QUE & START/QUE they run on the first available the list that has autostart enabled. If you set them /ON=*, then they will run on the node where you issued the command.

More important:
Do you have a really urgent reason to have them fail back when the failed node reboots?
The load caused by printqueues is negligable, the effort to fail them back by hand is not. I understand that your configuration DOES allow failover ( most important issue: all disks from which files might be printed must be mounted on all nodes where the queue might be running).
So essentially: Why care WHERE the queue is running, as long as it IS running.

As far as I can judge from here (meaning: I might be wrong but I don't think so) you are trying to solve a problem that has already been solved much more fundamentally by the VMS cluster engeneers.

hth,

Jan
Don't rust yours pelled jacker to fine doll missed aches.
Mac Lilley
Frequent Advisor

Re: OpenVMS cluster print queue setup

Hello

You could consider using generic and execution queues. Initialize the execution queues like this for example

$ init/queue system1$q1/on=system1::lta100:
$ init/queue system2$q1/on=system2::lta100:

and the generic queue

$ init/queue/generic=(system1$q1,system2$q1) q1

Print to the generic queue q1. Jobs then get transferred to either of the execution queues for processing. If say system1 crashes print jobs still get processed on system2$q1. When system1 reboots print jobs will then be processed by both execution queues. No need to move queues "by hand".

HTH

ML

M C_1
Advisor

Re: OpenVMS cluster print queue setup

David - start/queue/manager/on=(system1,system2,*) was issued way back when. According to the doc's it does not need to be reissued in startup unless a stop/queue/manager/cluster is issued.

Jan - Currently when I define queues, I set them up for one system only (i.e. /ON=(system1::xyz). I would like to re-init all queues with /AUTOSTART_ON=(sys1,sys2) so that they will failover on a system shutdown or crash.

The reason I want them to fail back once the other node is rebooted is because, we have between 600 and 650 queues. We are very print intensive. Lots of printing going on every minute,hour,day... My biggest consern is that printing continues to execute in the event we loose a system for a period of time. Second biggest consern, ballance print load between two systems.

Mac - I considered this option, but because of the sheer number of queues that we have this could be a bit complicated..

Thanks
MC

It is what it is!
Jan van den Ende
Honored Contributor

Re: OpenVMS cluster print queue setup

Well M C,

with us 800+ printer queues effectively all running on the same node present no problem at all. We print some 5000 pages daily, with peaks over 15000. Of course I don't know HOW intensive is "intensively used", but you have to get WAY over that before you should begin worrying.

I hope this give you some peace of mind.

Jan
Don't rust yours pelled jacker to fine doll missed aches.
Ian Miller.
Honored Contributor

Re: OpenVMS cluster print queue setup

I think the queues stay where they are without you stopping and starting them to move back. You define them /AUTOSTART=(node1::,node2::)

____________________
Purely Personal Opinion
M C_1
Advisor

Re: OpenVMS cluster print queue setup

Jan,
This does give me some piece of mind. I mean we have lots of printers, and I am not really sure how much paper we eat each day but its a bunch.

With respect to my question, I wanted this information to help analyze redundancy, availability, and failover of our cluster.

The documentation is not 100 % clear as to what failover means with respect to these queues(Crash/Shutdown).

Thanks for all the input.

MC
It is what it is!
M C_1
Advisor

Re: OpenVMS cluster print queue setup

Quick question regarding this old topic...

When you configure autostart on the cluster (in my case a 2 node cluster) does each system have to execute a start/queue on all queues for failover to be setup properly?

For example: Our current setup includes during startup; defining and configuring LAT and Multinet ports, then start individual queues on their respective nodes.

What I intend to do is re-configure all queues to be autostart. In the startup define and configure all ports on both systems, then enable autostart on both nodes in after the queue manager startes. Then start / queue each of the queues.

However, when both nodes boot do both nodes need to execute the start/queue portion?

Also on a system crash, the queues fail over to the other node. When the problem node comes back up does it really need to execute the start/queue part?

Can anyone out there share their config preferences?

Thanks,

MC
It is what it is!
Wim Van den Wyngaert
Honored Contributor
Solution

Re: OpenVMS cluster print queue setup

Q>However, when both nodes boot do both nodes need to execute the start/queue portion?

A> No. As long as the queue database is intact, none of the nodes have to do any queue setup. Only enable autostart/que is needed.

Q>Also on a system crash, the queues fail over to the other node. When the problem node comes back up does it really need to execute the start/que part?
A>Not when they are setup as autostart. Only the enable autostart/que is needed. Of course, you must make sure they are not stopped by stop/que.

Also : if you happen to have multiple system disks, make sure you spool to a shared disk.
Wim