Cups scaling

[Michael R Sweet]

Stef Coene wrote:
> Hi,
> 
> I'm looking for a solution to manage 600 network printers on a big
> AIX box (lots of CPU's / memory / disk space) that's part of a HA/CMP
> cluster.  Can CUPS handle this? I have no idea of the number of print
> jobs, but it will be a lot.

That should pose no problems.

> Also, is it possible to install it as part of a cluster?  I mean, all
> printing is done on 1 node of the cluster.  If this fails, a second
> node takes over the printing.  So how to handle:

CUPS doesn't support traditional cluster operation, but instead
has its own "implicit class" mechanism which can still work in
a cluster (just keep in mind that all CUPS servers are live at
the same time, not just a select few)

> - printer configuration: syncing the needed config files?  Or
> configuring the printers on both nodes?

Right now you have to manually manage this - it is usually just a
matter of mirroring /etc/cups and restarting the slave nodes.

> - print jobs: is it enough to mount the directory that holds the
> print jobs on the second node?  Will the second node pick up the jobs
> and reprint / resume them?

No, that's not how CUPS works.  I recommend reading the CUPS overview
document, but basically CUPS failsafe/load-balancing is provided
through implicit classes created by the clients - the clients hold
on to the print jobs until a server says they have been printed
successfully, and the clients determine which server in the class
to print to.

> To maintain the 600 printers, is it possible to store the
> configuration in a database / flat file?  So with 1 click on the
> buttom, the printers are generated.  I probably can script this
> myself, but maybe there is already a solution.

We have no built-in database support, but that is an oft-requested
feature.  We'll likely add support for this in CUPS 1.3, but don't
expect that any time soon (our focus is on getting 1.2 out now)

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products           mike at easysw dot com
Internet Printing and Publishing Software        http://www.easysw.com