3com and Cisco Switch compatibility issues

[dstepke]

Normally what happens is the switch locks up and I log thousands of congestions on the router ehternet port. Other times it just stops communications between devices hooked to it and the other switchs in the stack. The only way to get back on line is a cold boot to the Cisco switch. If I disconnect the Cisco switch all the problems go away. We have tried other Cisco switches just in case we had a bad switch. We have been told that the switches are compatible but could cause problems for us.

 

[gunthnp]

you might have porblem with auto dect try seting the speed

gunthnp

 

[TimRegester]

In simple ethernet terms minus the proprietary features ion the Cisco or 3Com side, the two are compatible.

If you connect the two via gigabit or fast ethernet it should work. The complications arise when you introduce the various proprietary elements, fast etherchannel on the Cisco side for example, uplinkfast etc. Make sure the Cisco is set for standards based Spanning tree, ensure that port speeds and duplex mode are hard set on the connection on both sides and there is no flow control set on either side. The link between the two should be full duplex there being thus no congestion. If 802.1Q VLAN tagging is used make sure this is the tagging mechanism used on the Cisco side.