[Qemu-discuss] Windows Server 2008 R2 slow printing

[David Gempton]

Just wanted to capture this...

I have a QEMU host running a mix of Linux and Windows virtual machines.

The Windows Server 2008 R2 virtual machines had became very slow to print.  It 
was taking up to 2 minutes to get a simple page out of the printer.  Seemed to 
be an issue with the spooler completing the delivery of the job to the printer. 
(Not sure why they slowed down.  They had been quick in the past).

To fix this I installed TAP network devices and gave the Windows machines their 
own IP addresses on the LAN.  This enabled me to install new printer queues 
that connected directly to the network printers.  Previous connections had been 
via the CUPS spooler on the QEMU host.

Using the TAP device instead of port redirection was also faster for Terminal 
Services Client (RDP) to connect to the Windows machines.

Little Note#  All machines on the LAN must have unique MAC addresses.  If you 
see strange results when you ping your VM's using TAP network devices take a 
look at the MAC addresses.  I ran in to this and wasted a couple of hours 
before I checked for duplicate MAC's.


In short.....  I suggest using TAP rather than port redirect.  Seems to be 
faster and more stable and reliable.

Thanks
Dave.