Do spanning-tree instances not show until trunks are plugged in ?

Posted on 2011-10-21
Medium Priority
Last Modified: 2012-05-12

I am setting up a production switch before I actually plug it in.  I am configuring spanning tree priorities for the switches.  This switch is NOT my primary root or secondary root switch.  The cmds I typed in so far are :

spanning-tree mode pvst
spanning-tree extend system-id
spanning-tree vlan 1,3-8,11-14,16,20,80-81,88,96,110,120,124,130 priority 57344
spanning-tree vlan 134,160,192,246-252,254-256,802 priority 57344
spanning-tree portfast default

But when I do a show spanning-tree, I get: No spanning tree instance exists.

Could it be because I have not plugged in any trunk ports yet (gotta wait for a maintenance window), or am I missing another cmd ?  I usually like to see some results before plugging something into production network, but if this is all I get for now, that is fine, I just want to be sure.

Thanks in advance
Question by:Elemental12
  • 2
LVL 17

Accepted Solution

rochey2009 earned 2000 total points
ID: 37007333
there needs to be an active link in each vlan or an active trunk link carrying the vlans before a spanning tree instance for each vlan exists.

the vlans also need to be created.

Author Closing Comment

ID: 37007533
Excellent, thanks for that.  The vlans exist, but the trunks are not plugged in yet.

LVL 17

Expert Comment

ID: 37007791
You're welcome.

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