Hi, I would like to understand the rationale and mechanism for this simple situation:
Please see diagram for details.
I have a new SwitchA that I need to connect to a production switch. Such SwitchA will serve hosts connected to vlan 19.
Then I establish trunking with the upstream, in production SwitchB using 'trunk vlan 21', since that is the vlan present on SwitchB. show cdp neig confirms devices are connected OK.
I notice that on SwitchA, the SVI int vlan 19 remains as up/down in spite of my 'no shut' command. I already shut down vlan 1.
Since SVI int vlan 19 is down, obviously I can't establish communications from SwitchA.
Therefore my question is, why int vlan 19 doesn't come up in this case on SwitchA?
