HP ZBook Dock multicast problems

At work my HP ZBook is fed through a nice thunderbolt docking station. I plugin one cable, and everything is connected: power, monitors, network, etc.

Then we started working on a C# project that uses multicast to communicate. I couldn’t receive any messages. I thought it was a VLAN issue first, so I took my notebook and plugged it in the wall, using the outlet a colleague uses who didn’t have these problems with the same software. Suddenly my communication was working as well. So I ‘proved’ that the problem was the network right?


After hours of switching cables in the patch panels, checking traffic in the logs of the switch, I suddenly realized that by taking my laptop to another location, I wasn’t using the docking station anymore. As it turns out the network port on the docking station seems to have problems with the multicast messages.

I don’t know why, but when I use the network interface on my laptop instead of the one on the docking station, the multicast communication is working fine.

So, save yourself hours of investigating this problem, and check your other ethernet port first ;-)

HP Laserjet 400 slow job processing

At the office, we got ourselves a nice HP Laserjet 400. Because it could do all things: print, fax, scan, and it should be OS X compatible too.


But when we wanted to print a document from our laptops, all connected to our gigabit LAN, it took ages before the printer finally started processing the job. So I installed some additional memory to the printer, which wasn’t too expensive anyways from eBay. Still no improvement. Some prints would come out fast, some prints didn’t. I thought it had something to do with processing the document to the right format for the printer. Isn’t that what PCL isn’t all about? Maybe the OS X drivers couldn’t talk to the laserjet in the most efficient way. Maybe the drivers aren’t that good after all.

Eventually I kind of gave up on the machine. My colleagues were already using our old laserjet 1320 anyways. The Laserjet 400 basically degraded to a really expensive scanner, at which it’s not very good either by the way.

Until one day extra people joined our team, and we moved the furniture around a bit in the office to create extra workspaces. This time I connected the printer through wifi, and now it seems that prints are coming through way faster.

So although I don’t understand why this is working better, just give it a try. It might work for you as well!