Maybe I was not clear about the problem. SW1 is the root for all Vlans. SW3 is the designated bridge for the link between SW2 and SW3. So, I expected port fa0/24 of SW2 be blocked for all Vlans. But it was forwarding for Vlan 1 and blocking for the others.
After erased the configuration, reset the switch and typed back the same configuration the state is blocking for all Vlans, as expected. Something strange happened with the software. Larry Letterman em 14/11/2002 15:29:31 Para: "[EMAIL PROTECTED]" cc: [EMAIL PROTECTED] Assunto: Re: Strange Spanning-Tree Behavior [7:57449] The root bridge will always be forwarding and the other end will be blocked in a network that is working correctly.... Larry Letterman Cisco Systems [EMAIL PROTECTED] wrote: Could you explain? Peter van Oene em 14/11/2002 10:28:04 Para: "[EMAIL PROTECTED]" cc: [EMAIL PROTECTED] Assunto: Re: Strange Spanning-Tree Behavior [7:57449] Only one side of a given link will block and thus what you are seeing is normal behavior. On Thu, 2002-11-14 at 11:00, [EMAIL PROTECTED] wrote: Does anybody know what is this? On interface fa0/24 of SW2, the state of spannnig-tree for Vlan1 was forwarding and for Vlan11 was blocking . All the values, bridge priority - port priority - port cost, were the default values. I expected both Vlans as blocking. The network is: SW1(fa0/22) -------(fa0/22) SW2(fa0/24) -------(fa0/24) SW3 (fa0/23)|__________________________________________|(fa0/24) After almost get crazy, I figured out that maybe the switch was crazy, so I erased the configuration, reload the switch and typed the configuration back. And it works fine. Before that, I just reload the switches, and there was no changes. SW2#sh spann int fa 0/24 Interface Fa0/24 (port 38) in Spanning tree 1 is FORWARDING Port path cost 19, Port priority 128 Designated root has priority 32768, address 0002.fd34.9180 Designated bridge has priority 32768, address 0005.326d.65c0 Designated port is 38, path cost 19 Timers: message age 0, forward delay 0, hold 0 BPDU: sent 31481, received 604975 SW3#sh spann int fa 0/24 Interface Fa0/24 (port 38) in Spanning tree 1 is BLOCKING Port path cost 19, Port priority 128 Designated root has priority 32768, address 0002.fd34.9180 Designated bridge has priority 32768, address 0005.326d.65c0 Designated port is 38, path cost 19 Timers: message age 2, forward delay 0, hold 0 BPDU: sent 605190, received 32565 SW 1 host SW1 ! interface FastEthernet0/1 duplex half speed 10 switchport access vlan 11 ! interface FastEthernet0/2 duplex half speed 10 ! interface FastEthernet0/3 duplex half speed 10 ! interface FastEthernet0/4 duplex half speed 10 ! interface FastEthernet0/5 duplex half speed 100 ! interface FastEthernet0/22 description *** connection to SW2 *** switchport mode trunk ! interface FastEthernet0/23 description *** connection to SW3 *** switchport mode trunk ! Int vlan 1 ip ad 1.1.1.254 255.255.255.0 SW 2 host SW2 ! interface FastEthernet0/22 description *** connection to SW1 *** switchport mode trunk ! interface FastEthernet0/24 description *** connection to SW3 *** switchport mode trunk ! Int vlan 1 ip ad 2.2.2.254 255.255.255.0 SW 3 host SW3 ! interface FastEthernet0/23 description *** connection to SW1 *** switchport mode trunk ! interface FastEthernet0/24 description *** connection to SW2 *** switchport mode trunk ! Int vlan 1 ip ad 3.3.3.254 255.255.255.0 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57462&t=57449 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]