I want to create new vlan id but i get message "% Failed to create VLANs xxxx
Spanning-tree extend system-id need to be enabled." If i enable that is there going to be any changes or break in spannintree topology.
spanning-tree extend system-id
has an effect on the way the bridge-id for each vlan/instance is created.
a different mac address for each vlan taken from internal block
same priority value for all vlans
new way:= extend systemid
use only one MAC but priority is built as
base_value + vlan#
base_value is a multiple of 4096.
bridge-id = priority+ MAC address
it changes the bridge-id for each vlan this may change the root bridge in some vlan.
But the impact should be limited
the reason for this is to avoid to waste MAC addresses.
your switch has probably used all internal MAC addresses.
Hope to help
I have 3 distro switch have a priority value of 16384. The main distro switch connected to my router has a value of 8192.
I, too, received the same message when I attempted to create VLAN1725. I have successfully created the SVI for the said VLAN. Should I enable spanning-tree extend system-id during after-hours? You mentioned that the impact is limited, what's the worst thing that could happen?