[duboy]

We have a network that is...8 macs big going through multiple hubs and a router to connect to DSL and share the connection. there are iBook and iMacs. all the computers are set up to use DHCP. can anyone explain why if we move iMacs to certain jacks, they won't see the network, or get an IP? but if we move around the iBooks, they work at all of the jacks? it's a very odd situation, just wondering if anyone has heard of this before. Thanks!

[ghporter]

Perhaps some of the jacks are wimpy? It's as good a guess as any.

Have you considered simplifying things and converting to a single, 8-port gateway router? The 8 port switch beats the heck out of multiple hubs, everything is guaranteed to be in the same subnet, and you only have one box to deal with. They're not as expensive as I thought they'd be. Check out this page for one example.

[BkueKanoodle]

Sounds like you have a lot of interference on the network, and the extra hubs are just going to make it worse. Some NIC's are better then other at filtering out the noise, hence why you're probably seeing the ibook/imac difference. I agree with the other poster, get rid of some of those hubs. Ideally, you should never plug more then 2 or 3 hubs together and hope to get reliable connections throughout the entire network.

[merlin]

Wow, that is weird.

Don't know what the cause is, but I do agree with the other posters. You're more likely to run into packet collisions and congestion with hubs. A router/switch is a lot more efficient since it can route packets destined for a paticular computer directly to it rather than broadcast to all the ports like a hub would.

Things to consider...

-Maybe the iMacs have problems with auto-sensing 10 vs 100 base-T?

-Are you using the same types of RJ45 cables? Have you tried swapping cables around to see if the cable you're using matters?

-Is it only the uplink port on the hub that causes problems or do other ports have problems as well?

Good luck!