cisco: sharing vlan information
Hi. I'm learning cisco IOS on my own (with some spare equipment) and was wondering about this:
I understand that switches can share vlan-tagged data over interfaces set to trunk mode and dot1q. However, how is it that switches share (meta-)information about the vlans (e.g., name of the vlans) without configuring all of them repeatedly each switch?
I looked at a production switch once, and "show vlan" listed about 60 vlans with names and other information. But only two or three vlans were actually defined (and used) in the run config itself. What mechanism and command causes the vlan metadata to be shared?
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