How to Bring Up a SVI Interface Cisco Switch
SVI must meet all of the following conditions to transition to the full “up/up” state.
1- The VLAN must exist and be active in the VLAN database.
2- At least one switched port in the VLAN (access or trunk) must be up.
3- That port must be in the STP forwarding state.
Sometimes it is necessary to have that VLAN interface up even if there are no devices or ports using that VLAN
simply forced the VLAN into an “up/up” state. Issuing the “no autostate” command on the VLAN interface will bring the interface up. Basically, the command just tells the VLAN interface to ignore the above mentioned prerequisites. Note: This command is only available in certain IOS images.