Catalyst Blade Switches 3020 for HP

[cosimotodaro]

Hi all,

We have 12 Catalyst Blade Switches 3020 for HP running IOS Version 12.2(55)SE.  In the configuration of these switches I see the statement shown below.

no spanning-tree vlan 34,45-55,70,600,643,840,843-850

The 12 blade switches are configured as VTP clients and running VTP V2.  I did not configure the statement shown above.  It appered by itself.  And even if I delete it, it will reapper.  (The blade switches are interconnected to two 6509s.  The two 6509s are the STP root and VTP bridges. I configure Vlans and STP on the 6509s).

Does anyone know why the statement above appers on the blade switches 3020s?

I mean I use other Cisco switches such as 3750s and 3560s and I have never seen the statement above appear by itself.

Thanks

[paul driver]

Hello,

As you may be aware that  the no spaning-tree vlan x x x x means stp is disabled for those vlans and no loop detection or prevention will be available.

I suppose this command could be invoked if currently those vlans stated not currently active, but I cannot not see as to why you would want to disable stp and incur the wrath of broadcast storms etc..

I haven't check CCO but I am assuming on the 3020 switches stp isn't disabled by default either.

res

Paul

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[cosimotodaro]

Hi,

Thanks for your answer.  No, I don't want STP to be disabled.  On the contrary that's what worries me.  That's why I said in the post above that I did not run the command "no spanning-tree vlan ...".  One day when I saw those statements in the configuration, I manually removed them.  But, they reappered again.  I think it was after a reboot that they reappered.  It sound a kind of crazy.  But, it is so.

Now what worries me is the following.  I have checked all 12 blade switches and some (not all) of the vlan tha are supposed to have an instance of STP running is not acually running because of the statement "no spanning-tree vlan ..."  So, this is worring and I can't find any information on the Internet either.

[serge123]

Hi,

I am using per vlan spanning tree (rapid-pvst) on my blade and it works great.

spanning-tree vlan vlan_id priority priority (Optional) Sets the STP bridge priority;

<0-61440> bridge priority in increments of 4096

Thanks,

[paul driver]

Hi ,

Enable stp for all vlans and dont forget to save your configuration. If you have trunks make sure all the allowed vlans for those trunks has the stp instance enabled.

res

Paul

http://www.cisco.com/en/US/docs/switches/blades/3020/software/release/12.2_55_se/command/reference/cli3.html#wp1947142

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