I have a location that has a 3745 and a 3640 connecting to 3550 and 3524 switches. I tried to convert the routers from ISL to 802.1q and had problems. The routers could see the other facilities but the devices at the location that I was trying to convert couldn't see the other locations. I shut down the trunks and even powered off and back on the routers and main switches with no luck. Converted the trunks back to ISL and everything came back instantly. The ports on the switches have the "SWITCHPORT TRUNK ENCAP DOT1Q" and "SWITCHPORT MODE TRUNK" statements.
[toc:faq]The ProblemOn traditional switches whenever we have a trunk
interface we use the VLAN tag to demultiplex the VLANs. The switch needs
to determine which MAC Address table to look in for a forwarding
decision. To do this we require the switch to do...
[toc:faq]Introduction:Netdr is a tool available on a RSP720, Sup720 or
Sup32 that allows one to capture packets on the RP or SP inband. The
netdr command can be used to capture both Tx and Rx packets in the
software switching path. This is not a substitut...
IntroductionOSPF, being a link-state protocol, allows for every router
in the network to know of every link and OSPF speaker in the entire
network. From this picture each router independently runs the Shortest
Path First (SPF) algorithm to determine the b...