Steps to convert two standalone switches to VSS switches

  (by default all switches are operating at standalone mode)  

1. optional - save configs
         >> assuming that these boxes are new, no configs need to be save
2. Configure each chassis as VSS
3. Configure VSSL peer
4. Convert!

    == Step 2 ==   assigning switch domain

note:  once vss is completed, # will not be in config. However, you must ensure that those numbers are NOT the same. 

The priority (number between 1 - 255) allows the switch to elect an "active" member.
Switch1(config)#
 switch virtual domain 40
  swtich 1

  switch 1 priority 150

Switch2(config)#
 switch virtual domain 40
  switch 2

  switch 2 priority 100

>> higher priority will take over active state when it loads. 

    == Step 3 ==

  Configuring VSL Port channel and ports    (VSL = Virtual Switch Links)

create Port Channels for VSLswitch1(config)#
 int po100
  description VSL 1
  switch virtual link 1
  no shut

 switch2(config)#
  int po200
  description VSL 2
  no shut

>> each switch needs a different port-channel group to avoid having the configs overwritten when the switches are converted and the configs are combined together.

add them to the physical InterfacesSwitch1(config)#
 int range Te1/1/1 - 2
  description VSL to switch 1
  channel-group 100 mode on

Switch2(config)#
 int range Te1/1/1 - 2
  description VSL to switch 2
  channel-group 200 mode on

    == Step 5 ==
     Converting it to VSS!  (use same commands on both switches)

checking platform (optional)

switch1&2#
 show platform hardware pfc mode

>>if it is not set to pfc3c then:

Switch1&2(config)#
 platform hardware vsl pfc mode pfc3c

converting to VSS

if you watch the conversion taking place, you can see the active & standby election process and will be able to watch the ports change from 1/1 to 1/1/1.

Switch1&2#
 switch convert mode virtual
 yes

this convert command automatically saves config so you dont have to worry about saving them. (as long as whatever you had before the conversion was saved)

also, Switch 1 and Switch 2 do no have to be converted at the same time. It is interesting to watch the processes a switche goes through to become a VSS switch instead of standby. They will both be VSS after both of them have been converted.

These two are the requirements for having a VSS

Switch1&2(config)#
 redundancy
  mode sso

=> this is done by default onces switch domains are configured.

Switch1&2(config)#
 router ospf 10
  nsf

=> can be done after conversion