By default, BGP will drop a route if it sees it's own AS in the advertisement. Allowas-in allows this to happen. You'll see this mainly when MPLS LSP is between you and another site you own. If you want to run BGP between the 2 locations, your location will not allow the traffic inbound. Some providers will override your AS and put theirs in its place so you will get the update. If you know for a fact that you won't get a routing loop, you can use the "allowas-in" with no worries, but it pretty much disables BGP's protection that I stated above.
[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...