 10 !Command: show running-config interface port-channel10 !Time: Mon Jan 17 :57:20 2011 version 5.0(2)N2(1) interface port-channel10 description BladeServer switchport mode trunk vpc 10 switchport trunk allowed vlan 10,20,30,40 Chapter 18: Cisco Nexus spanning-tree port type edge trunk speed 1000 Holy crap, it worked! That's an actual quote from the first time I saw config-sync work. Hey, you get a little goofy after sitting in a windowless lab for three days. Config-sync is fun and all, but let's look at the dangers. The configuration you enter is visible in the running config, as we can plainly see from the example above, but it's not really there. The configuration we've entered exists in the config-sync database. You can see what's in this database by using the show running-config switch-profile command: NX-5K-1# sho running-config switch-profile switch-profile GAD sync-peers destination 10.0.0.2 interface port-channel10 spanning- - tree port type edge trunk Meanwhile, the running config looks normal, with only this line to reveal the dangers lurking beneath: NX-5K-1# sho run begin switch-profile switch-profile GAD sync-peers destination 10.0.0.2 Doesn't look very dangerous, does it? Imagine that you've hired a new junior engineer. Better yet, imagine that you are the new junior engineer. Being the young, headstrong networking demigod that you are, you feel that the switch-profile command clearly has no purpose, SO you decide to summarily delete it. Think this scenario is implausible? I can think of no fewer than five- no, wait-seven instances where junior engineers have come into a shop and decided that they would "clean things up," only to cause cata- strophic outages. Don't be that guy: NX-5K-1# conf sync Enter configuration commands, one per line. End with CNTL/Z. NX-5K-1 1(config-sync)# no switch-profile GAD ? all-config Deletion of profile, local and peer configurations local-config Deletion of profile and local configuration Hmm. That's odd. I'll pick local, because I wouldn't want to break anything: 