Two hours' advice on moving to twisted pair
November 16, 2005
In the span of less than two hours, the 3000-L mailing list and newsgroup delivered a series of user reports today on how to move away from coaxial network connections and onto more modern twisted pair wiring. In wiring parlance, this is moving from 10-Base-2 networks (called ThinLAN in the 3000 world) to 10-Base-T — the T standing for twisted pair.
Once James Byrne asked how to do this upgrade to his disaster recovery system, a quartet of net vets explained the process. Denys Beauchemin chipped in first:
It’s been several years since I have done this, but it’s easy. You have the pull the MFIO card and right inside, next to the outside panel itself, you will find a rather sizable (2 inches) block that you need to lift and place in the other position, if I recall correctly. Then you need to get an inexpensive ($5-$35) transceiver and plug it into the MFIO card. You then plug your RJ-45 into the transceiver.
Tracy Johnson confirmed this advice;
Exactly what Denys said (although I thought the block was smaller.) Instead of a transceiver, you “could” use one of those fat AUI cables long enough to go to a hub or switch. But I don’t think they make hubs or switches with those ports anymore. So you’re better off with a cheap transceiver.
Jeff Kell, curator of the 3000-L host system (which we've learned is a Windows 2003 system, not a Linux server) added a time-saving alternative next.
You can also use a "media converter", which is essentially a 2-port hub with a BNC and an RJ45. We went that route when we still had a rack of DTCs and didn't want to buy that many freakin' transceivers :-) It fixed them all with one fell swoop. Ours were Allied Telesyn, who made a variety of converters and media converters. Try http://www.alliedtelesyn.com/products/features.aspx?cid=4
Allied Telesyn products are sold through Best Buy for Business, among other outlets.
Finally, HP support engineer James Hofmeister added more hands-on details on how to make that swap inside the 3000's cabinet, and told Byrne what contingencies to watch out for:
Take care to discharge static before touching the card. Usually having a hand in contact with the metallic part of the system case before touching the card is sufficient. On removing and re-installing the Console-LAN card, take great care to align the card in the cage slot before re-inserting. The part that extends the furthest off of the card is a fuse which protects the card from the AUI interface; if you bend/break this fuse, the AUI interface does not work 8-)
The 8-pin jumper you will be moving is about 3/4 of an inch long and you will be moving it from INT to EXT. Note: This jumper is very close to the location of the AUI 15-pin connector.
What contingencies should you provide for? A) blow the fuse... prepare to go back and run ThinLAN, or make a trip to Radio Shack? to replace the fuse. B) blow the card.... have a spare before you start?
Four experts, less than two hours' response. You might think about that the next time you wonder who's going to support the HP 3000 during 2007. Some fundamentals, even those hidden inside the 3000's cabinet, are just an e-mail message away.