Cisco: how to set up switch port bundling for redundancy

[ATC]

CCO documentation can be quite confusing on this point, so here's how we did it on a pair of older 2900 series switches.

Note that this solution gives redundancy but not added link capacity. If you have alternate solutions to offer, please email them to floyd@atc.no

[ATC]

Start with all of the bundled ports in "shutdown" mode, plug in all the cables, and then configure one port at the time at both ends:

interface FastEthernet0/2
 port group 1
 switchport trunk encapsulation isl
 switchport mode trunk
!
interface FastEthernet0/3
 port group 1
 switchport trunk encapsulation isl
 switchport mode trunk
!
interface FastEthernet0/4
 port group 1
 switchport trunk encapsulation isl
 switchport mode trunk
!