Re: Discussion on GRE Tunnel and GRE Tunnel Configuration
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Rolf's references cover GRE very well.
Just wanted to emphasis, some of the "optional" settings can be advantageous. First, I like using "keepalive 1". This insures tunnels goes "down" if reachability is lost to other side. This is handy even on links where you're running a dynamic routing protocol if you're also running SNMP monitoring, as the latter usually "alarms" well when an interface goes down and perhaps not so well when a routing protocol loses a neighbor.
Using mss-adjust (if supported) and the correct MTU related commands helps deal with fragmentation issues which often are adverse to performance. Do, though, keep in mind, IP/TCP overhead can be larger than 40 bytes, so setting mss-adjust to 1436 isn't a guarantee of success even with end-to-end Ethernet supporting 1500 MTU.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...