High Volume, Many Printer setup

[Michael Sweet]

Kelly Sauke wrote:
> ...
> 1).  If one of the cups machines goes down, when the client hits the
> BrowseTimeout it starts removing the printers from that host.  While
> the client is removing all the printers, all other printing commands
> (lp, lpstat, etc) lock up and wait for this process to get done.
 > ...

That shouldn't happen.  Printer timeouts will be staggered over the
browse interval period, and they take essentially no time at all to
process.  Certainly no time for the high-end systems you are using!

The general rule-of-thumb is to set the BrowseInterval to be greater
than the number of printers, and the BrowseTimeout to be 3 times
the interval.

> 2).  Say we bump the BrowseTimeout up so that printers don't get
> removed right away if one of the servers goes down.  Now say cups02
> is down but the printer definitions still exist on the client
> (because it hasn't hit the BrowseTimeout yet).   I queue multiple
> jobs to the same printer.  The first job will get sent to cups01.
> Say that job takes a long time to print.  The next job queued to the
> same printer gets sent to the down cups02.  After about 5 seconds,
> this job is canceled by cups instead of staying in the queue to go to
> cups02 when it comes back or going to cups01 when it has finished
> printing.  Shouldn't this job stay queued while there is a valid
> printer definition?  I can post the logs from the client showing the
> job cancellation if that would be helpful.

That is strange - when the client's ipp backend cannot connect to
the remote printer, it should immediately stop trying if the job
is queued on an implicit class and retry the job on the next printer
in the class.

If you can post a snippet of the error_log with the LogLevel set to
debug, that might be useful...

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