09-28-2009 07:01 AM - edited 03-06-2019 07:54 AM
I'm at a loss, I have spent a few hours looking at my spanning-tree and I cannot figure out why my ports are showing "Bound (RSTP)".
Configurations match across the board, same VLAN's, same VLAN names, same revision number, same MST name, what am I missing?
Dist A:
spanning-tree mode mst
spanning-tree loopguard default
spanning-tree portfast bpduguard default
spanning-tree portfast bpdufilter default
spanning-tree extend system-id
!
spanning-tree mst configuration
name SIS
revision 1
instance 1 vlan 1-3, 173-174, 200-201, 2005
instance 10 vlan 1011-1019
instance 20 vlan 1021-1029
instance 30 vlan 1031-1039
instance 40 vlan 1041-1049
instance 50 vlan 1051-1059
instance 60 vlan 1061-1069
instance 70 vlan 1071-1079
instance 80 vlan 1081-1089
instance 90 vlan 1091-1099
!
spanning-tree mst 0-1,10,20,30,40,50,60,70,80,90 priority 24576
VTP Version : running VTP2
Configuration Revision : 0
Maximum VLANs supported locally : 1005
Number of existing VLANs : 8
VTP Operating Mode : Transparent
VTP Domain Name : SIS
VTP Pruning Mode : Disabled
VTP V2 Mode : Enabled
VTP Traps Generation : Enabled
Dist B:
spanning-tree mode mst
spanning-tree loopguard default
spanning-tree portfast bpduguard default
spanning-tree portfast bpdufilter default
spanning-tree extend system-id
!
spanning-tree mst configuration
name SIS
revision 1
instance 1 vlan 1-3, 173-174, 200-201, 2005
instance 10 vlan 1011-1019
instance 20 vlan 1021-1029
instance 30 vlan 1031-1039
instance 40 vlan 1041-1049
instance 50 vlan 1051-1059
instance 60 vlan 1061-1069
instance 70 vlan 1071-1079
instance 80 vlan 1081-1089
instance 90 vlan 1091-1099
!
spanning-tree mst 0-1,10,20,30,40,50,60,70,80,90 priority 28672
VTP Version : running VTP2
Configuration Revision : 0
Maximum VLANs supported locally : 1005
Number of existing VLANs : 8
VTP Operating Mode : Transparent
VTP Domain Name : SIS
VTP Pruning Mode : Disabled
VTP V2 Mode : Enabled
VTP Traps Generation : Enabled
Random Closet:
spanning-tree mode mst
spanning-tree loopguard default
spanning-tree portfast bpduguard default
spanning-tree portfast bpdufilter default
spanning-tree extend system-id
!
spanning-tree mst configuration
name SIS
revision 1
instance 1 vlan 1-3, 173-174, 200, 2005
instance 10 vlan 1011-1019
instance 20 vlan 1021-1029
instance 30 vlan 1031-1039
instance 40 vlan 1041-1049
instance 50 vlan 1051-1059
instance 60 vlan 1061-1069
instance 70 vlan 1071-1079
instance 80 vlan 1081-1089
instance 90 vlan 1091-1099
VTP Version : running VTP2
Configuration Revision : 0
Maximum VLANs supported locally : 1005
Number of existing VLANs : 8
VTP Operating Mode : Transparent
VTP Domain Name : SIS
VTP Pruning Mode : Disabled
VTP V2 Mode : Enabled
VTP Traps Generation : Disabled
The ports are completely mix-matched, Dist A to any closet shows fine, but any closet to Dist A show "Bound (RSTP)".
Dist B to any closet shows "Bound (RSTP)" and any closet to Dist B shows fine...
I attached a diagram to help with the visual. The red arrows indicate a Boundary problem and the direction, green arrows show proper MST boundary. You can see the boundary flows one way, I didn't mark ever connection, but they are all the same.
Thanks,
Craig
I attached a diagram to help with the visualization.
Solved! Go to Solution.
09-28-2009 08:33 AM
In random closet config, I see vlan 201 being mapped to instance 0 instead of instance 1 in dist A & B.
You can use the command "show spanning-tree mst configuration digest" to see the configuration digest sent in MST BPDUs. That's probably simpler to compare the MD5 digests when you have a large configuration, rather that checking them one line at a time;-)
HTH,
Francois
09-28-2009 08:33 AM
In random closet config, I see vlan 201 being mapped to instance 0 instead of instance 1 in dist A & B.
You can use the command "show spanning-tree mst configuration digest" to see the configuration digest sent in MST BPDUs. That's probably simpler to compare the MD5 digests when you have a large configuration, rather that checking them one line at a time;-)
HTH,
Francois
09-28-2009 08:45 AM
That is why you passed your lab and I didn't :) Thanks for the second set of eyes and the "show spanning-tree mst configuration digest" command!
Craig
09-28-2009 09:06 AM
I can remember a case escalated from the TAC, where no-one could see the difference between two regions. I was so desperate that I ended sniffing the BPDUs exchanged to check if they were correctly formed. There was a difference in the region name that I could only see because the sniffer output was in hexadecimal. For some reason, my brain just couldn't read the difference between the two region names even after checking 20 times. And so did a good 10 engineers before me. We should not overestimate the capability of the human race at comparing MST configurations, don't take it personally;-)
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