May be a Spanning Tree Protocol issue. A lot of the older 3Com switches were set to STP disabled when they shipped from the factory, you had to turn it on. That meant you could plug in a workstation and the switchport would go right to forwarding traffic. Only recently (last 2 or 3 years or so) did they start shipping with STP enabled, and I think Spanning Tree FastPort enabled on 10/100 connections. (FastPort is their version of Cisco's PortFast.)
Cisco seems to always enable STP by default in their switches. This could result in a 30-50 second delay when link is initiated; if computer boots fast and uses DHCP, maybe the computer's not getting an IP address and defaulting to something that's not going to route on your network. May also explain why your HP network-attached printer works: it probably has a static IP address.
Try enabling "spanning-tree portfast" on each of the Cisco switches' ports where computers are having problems. This jump-starts the switch port to forwarding when link is first established.
If that doesn't fix it, another possibility is the drivers on the computers' network adapters may not be autonegotiating speed and/or duplex correctly. Check to make sure you have the latest ones.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.