SuperStack II + HPJetdirect = Host Not Available

[piperent]

I have several HPJetDirect Print servers (both models 170x and EX Plus) connected to a Unix network. They are all connected thru a 3Com superstack II (model 3C250B-TX) along with several PC's. I have no problem connecting any PC to the Unix Server, but cannot get ANY of the HPJetDirects to be recognized by the Unix host when connected thru the SuperStack II. Whenever I PING the Jet Directs, it returns a 'Host Not Available' message. Here's the rub. I removed the 3Com SuperStack and replaced it with two other hub devices (a smaller 3Com 8 port device and a 4 port Netgear) and the JetDirects are immediately recognized by the Unix Host and work properly.

So, is there something special about the SuperStack II's that has to be considered (cabling, configuration, or something of that sort) that is not apparent? I noticed a black switch on the back (D - E) that is set to E on my device. My assumption is that this is for stacking devices together, but does it have any effect on a single hub device with no others attached via the 'up' or 'down' port? Since PC's and Unix can communicate freely thru the SuperStack, I would expect a print server to be able to so also.

Any input will be appreciated. This is the first time I've tried using these 3Com devices, but have connected many a network print server thru other, similar type hubs.

Thanks
JP

 

[torontolatinmale]

Hi Pi!!
Well, the only thing I think of is the port negotiation, full/half duplex, also whether or not this switch is transmitting POE. Also the power quantify transmitting on those ports.
Review what your print server consume.
Good luck!