Spanning-tree now producing a block in new IOS

[gkeel]

I have several Cisco Catalyst 3560 switches configured with multiple VLANs.  Originally I was running IOS c3560-I9-mz.122-20.se4 and when I attached a Cisco 3550 switch in a basically unconfigured state to one of the access ports on the 3560, it would connect and act like it was a dumb hub or switch attached.

I just updated the Cisco 3560 switches to IOS c3560-ipbasek9-mz.122-53.SE.  Now when I connect the 3550 switch to the 3560, I get the following on the console of the C3550:

  00:08:04: %SPANTREE-7-RECV_1Q_NON_TRUNK: Received 802.1Q BPDU on non trunk FastEthernet0/24 VLAN1.
00:08:04: %SPANTREE-7-BLOCK_PORT_TYPE: Blocking FastEthernet0/24 on VLAN0001. Inconsistent port type.

Using something like a cheap Netgear 16 port 10/100 switch does not do this and works just fine.  However, I use the unconfigured 3550 switch as part of my traveling classroom setup and really need it to act as it did before so that I don't have to configure one of the ports as a trunk port and then chnage vlans on the switch each time I move to a new location with different vlans.

Any ideas on how I could do this?

Thanks.

Gene

[gkeel]

I'll try that in the morning.  That sounds like it would be the optimal solution for me if it

works.  I really don't have to worry too much about other things because the

switch gets plugged into awal jack and then all of the class laptops get plugged into it.

Shouldn't have to worry about that.

[gkeel]

Setting "no spanning-tree vlan 1" worked beautifully.  I guess it really did kind of turn the switch into just a dumb set of extra ports.

Thanks to all who took the time to provide ideas and support on this! It is much appreciated!

Gene