t switch. The interface configuration associated with the old switch number will remain as a provisioned configuration. Do you want to continue?[confirm] Changing Switch Number 2 to Switch Number 1 New Switch Number will be effective after next reboot Chapter 19: Catalyst 3750 Features As it says, I need to reboot, SO I write mem and reload. After I do so, my interfaces are properly named. Hooray! IOS-3750#sho ip int brie Interface IP-Address OK? Method Status Protocol Vlan1 unassigned YES NVRAM administratively down down GigabitEthernet1/0/1 unassigned YES unset GigabitEthernet1/0/2 unassigned YES unset GigabitEthernet1/0/3 unassigned YES unset GigabitEthernet1/0/4 unassigned YES unset [ output truncated --] But there's a problem. First, the output of show switch detail shows two switches, even though the switch is obviously switch 1: IOS-3750#sho switch detail Switch/Stack Mac Address : dc7b.94dd.2280 Current Switch# Mac Address Priority Version State Master dc7b.94dd.2280 Ready Member (0000.0000.0000 Provisioned That will make sense as soon as you look at the configuration and realize that the configuration for all your interfaces has disappeared. Well, technically, that isn't ac- curate. The configuration still exists for those interfaces, but the switch considers switch 2 to be absent, which is why the MAC address is all zeros and the status "provisioned." You can see the interfaces in the configuration with other show commands: IOS-3750#sho ip int brie I beg 1/0/50 GigabitEthernet1/0/50 unassigned YES unset GigabitEthernet1/0/51 unassigned YES unset GigabitEthernet1/0/52 unassigned YES unset GigabitEthernet2/0/1 unassigned YES unset GigabitEthernet2/0/2 unassigned YES unset [ output truncated --] remember-this command will not renumber your interfaces and move the con- figurations. You'll need to do that yourself. Interface Ranges Interface ranges are a very useful addition to IOS. Instead of entering the same com- mands on multiple interfaces, you can specify a range of interfaces and then enter commands o