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Cisco 3750 MSTP configuration

AndreK
Beginner
Beginner

‎09-30-2020 01:32 PM

Hi, guys. I can not understand. On the Level 2 switch, for instance 0 root is indicated correctly, but for the rest instances the Level 2 switch points to itself.

 

Why is that? Is this correct?

 

My configuration

Cisco WS-C3750X-48P iOS 12.2(55)SE13

switch Level 1

 

spanning-tree mode mst
spanning-tree logging
spanning-tree extend system-id
spanning-tree pathcost method long
!
spanning-tree mst configuration
 name MSTP-R01
 revision 1
 instance 1 vlan 700
 instance 2 vlan 101, 1210, 1220-1223, 1230, 1240, 1250
 instance 3 vlan 1300, 1310, 1320, 1330, 1399
 instance 4 vlan 100
 instance 5 vlan 1010, 1030, 1040
 instance 6 vlan 2020
 instance 7 vlan 500
 instance 8 vlan 600
 instance 9 vlan 1110, 1120
 instance 10 vlan 10, 310, 320, 330, 340
!
spanning-tree mst 0-10 priority 28672

Cisco  WS-C3750-48P 12.2(55)SE10

Level 2

spanning-tree mode mst
spanning-tree logging
spanning-tree extend system-id
spanning-tree pathcost method long
!
spanning-tree mst configuration
 name MSTP-R01
 revision 1
 instance 1 vlan 700
 instance 2 vlan 101, 1210, 1220-1223, 1230, 1240, 1250
 instance 3 vlan 1300, 1310, 1320, 1330
 instance 4 vlan 100
 instance 5 vlan 1010, 1030, 1040
 instance 6 vlan 2020
 instance 7 vlan 500
 instance 8 vlan 600
 instance 9 vlan 1110, 1120
 instance 10 vlan 10, 310, 320, 330, 340
!
spanning-tree mst 0-10 priority 61440

Level 2 show spanning-tree

sw-kv-net-as43#sho spanning-tree mst 0

##### MST0    vlans mapped:   1-9,11-99,102-309,311-319,321-329,331-339
                               341-499,501-599,601-699,701-1009,1011-1029
                               1031-1039,1041-1109,1111-1119,1121-1209
                               1211-1219,1224-1229,1231-1239,1241-1249
                               1251-1299,1301-1309,1311-1319,1321-1329
                               1331-2019,2021-4094
Bridge        address 0015.c6dc.cc80  priority      61440 (61440 sysid 0)
Root          address 44d3.ca5b.e600  priority      28672 (28672 sysid 0)
              port    Gi1/0/1         path cost     20000
Regional Root this switch
Operational   hello time 2 , forward delay 15, max age 20, txholdcount 6
Configured    hello time 2 , forward delay 15, max age 20, max hops    20

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Root FWD 20000     128.1    P2p Bound(RSTP)
Gi1/0/3          Desg FWD 20000     128.27   P2p
Fa1/0/43         Desg FWD 200000    128.47   P2p Edge
Fa1/0/44         Desg FWD 200000    128.48   P2p Edge
Fa1/0/45         Desg FWD 200000    128.49   P2p Edge
Fa1/0/46         Desg FWD 200000    128.50   P2p Edge
Fa1/0/47         Desg FWD 200000    128.51   P2p Edge
Fa1/0/48         Desg FWD 200000    128.52   P2p Edge

sw-kv-net-as43#sho spanning-tree mst 1

##### MST1    vlans mapped:   700
Bridge        address 0015.c6dc.cc80  priority      61441 (61440 sysid 1)
Root          this switch for MST1

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Mstr FWD 20000     128.1    P2p Bound(RSTP)

sw-kv-net-as43#sho spanning-tree mst 2

##### MST2    vlans mapped:   101,1210,1220-1223,1230,1240,1250
Bridge        address 0015.c6dc.cc80  priority      61442 (61440 sysid 2)
Root          this switch for MST2

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Mstr FWD 20000     128.1    P2p Bound(RSTP)
Labels:
3 Replies 3

balaji.bandi
VIP Community Legend VIP Community Legend
VIP Community Legend

‎09-30-2020 01:59 PM

If you looking at VLAN 700, they are not allowed in the port-channel so they become locally root bridge?

 

is this what you looking for, sorry if i miss understood your question here?

 

also, post Level 1 spanning-tree output to understand better

BB

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AndreK
Beginner
Beginner
In response to balaji.bandi

‎09-30-2020 02:23 PM

Sorry for my english.  Why are 1, 2, 3 instances has different root at Level 2 switch?

 

Level 1 sho spanning-tree mst 0,1,2 

sw-kv04-net-cr03#
sw-kv04-net-cr03#terminal length 0
sw-kv04-net-cr03#terminal width 132
sw-kv04-net-cr03#sho spanning-tree mst 0,1,2

##### MST0    vlans mapped:   1-9,11-99,102-309,311-319,321-329,331-339
                               341-499,501-599,601-699,701-1009,1011-1029
                               1031-1039,1041-1109,1111-1119,1121-1209
                               1211-1219,1224-1229,1231-1239,1241-1249
                               1251-1299,1301-1309,1311-1319,1321-1329
                               1331-1398,1400-2019,2021-4094
Bridge        address 44d3.ca5b.e600  priority      28672 (28672 sysid 0)
Root          this switch for the CIST
Operational   hello time 2 , forward delay 15, max age 20, txholdcount 6 
Configured    hello time 2 , forward delay 15, max age 20, max hops    20

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Desg FWD 20000     128.1    P2p 
Gi1/0/2          Desg FWD 20000     128.2    P2p Pre-STD 
Gi1/0/3          Desg FWD 20000     128.3    P2p Pre-STD 
Gi1/0/4          Desg FWD 20000     128.4    P2p Pre-STD 
Gi1/0/5          Desg FWD 20000     128.5    P2p Pre-STD 
Gi1/0/6          Desg FWD 20000     128.6    P2p Pre-STD 
Gi1/0/7          Desg FWD 20000     128.7    P2p Pre-STD 
Gi1/0/8          Desg FWD 20000     128.8    P2p Pre-STD 
Gi1/0/9          Desg FWD 20000     128.9    P2p Pre-STD 
Gi1/0/13         Desg FWD 20000     128.13   P2p Pre-STD 
Gi1/0/14         Desg FWD 20000     128.14   P2p Pre-STD 
Gi1/0/15         Desg FWD 20000     128.15   P2p Pre-STD 
Gi1/0/16         Desg FWD 20000     128.16   P2p Pre-STD 
Gi1/0/17         Desg FWD 20000     128.17   P2p Pre-STD 
Gi1/0/18         Desg FWD 20000     128.18   P2p Pre-STD 
Gi1/0/19         Desg FWD 20000     128.19   P2p Pre-STD 
Gi1/0/20         Desg FWD 20000     128.20   P2p Pre-STD 
Gi1/0/21         Desg FWD 20000     128.21   P2p Pre-STD 
Gi1/0/22         Desg FWD 20000     128.22   P2p Pre-STD 
Gi1/0/23         Desg FWD 20000     128.23   P2p Pre-STD 
Gi1/0/29         Desg FWD 20000     128.29   P2p Pre-STD 
Gi1/0/32         Desg FWD 20000     128.32   P2p Pre-STD-Cf 
Gi1/0/33         Desg FWD 20000     128.33   P2p Edge Pre-STD-Cf 
Gi1/0/36         Desg FWD 20000     128.36   P2p 
Gi1/0/38         Desg FWD 20000     128.38   P2p Pre-STD-Cf 
Gi1/0/42         Desg FWD 20000     128.42   P2p Pre-STD-Cf 
Te1/1/1          Desg FWD 2000      128.53   P2p 
Gi2/0/1          Desg FWD 20000     128.55   P2p 
Gi2/0/2          Desg FWD 20000     128.56   P2p Pre-STD 
Gi2/0/3          Desg FWD 20000     128.57   P2p Pre-STD 
Gi2/0/4          Desg FWD 20000     128.58   P2p Pre-STD 
Gi2/0/5          Desg FWD 20000     128.59   P2p Pre-STD 
Gi2/0/6          Desg FWD 20000     128.60   P2p Pre-STD 
Gi2/0/7          Desg FWD 20000     128.61   P2p Pre-STD 
Gi2/0/8          Desg FWD 20000     128.62   P2p Pre-STD 
Gi2/0/9          Desg FWD 20000     128.63   P2p Pre-STD 
Gi2/0/13         Desg FWD 20000     128.67   P2p Pre-STD 
Gi2/0/14         Desg FWD 20000     128.68   P2p Pre-STD 
Gi2/0/15         Desg FWD 20000     128.69   P2p Pre-STD 
Gi2/0/16         Desg FWD 20000     128.70   P2p Pre-STD 
Gi2/0/18         Desg FWD 20000     128.72   P2p Pre-STD 
Gi2/0/19         Desg FWD 20000     128.73   P2p Pre-STD 
Gi2/0/20         Desg FWD 20000     128.74   P2p Pre-STD 
Gi2/0/21         Desg FWD 20000     128.75   P2p Pre-STD 
Gi2/0/22         Desg FWD 20000     128.76   P2p Pre-STD 
Gi2/0/23         Desg FWD 20000     128.77   P2p Pre-STD 
Gi2/0/24         Desg FWD 20000     128.78   P2p Pre-STD 
Gi2/0/25         Desg FWD 20000     128.79   P2p Pre-STD 
Gi2/0/31         Desg FWD 200000    128.85   P2p Pre-STD-Cf 
Gi2/0/39         Desg FWD 200000    128.93   P2p Pre-STD-Cf 
Gi2/1/1          Desg FWD 20000     128.103  P2p 

##### MST1    vlans mapped:   700
Bridge        address 44d3.ca5b.e600  priority      24577 (24576 sysid 1)
Root          this switch for MST1

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Desg FWD 20000     128.1    P2p 
Gi1/0/2          Desg FWD 20000     128.2    P2p Pre-STD 
Gi1/0/3          Desg FWD 20000     128.3    P2p Pre-STD 
Gi1/0/4          Desg FWD 20000     128.4    P2p Pre-STD 
Gi1/0/5          Desg FWD 20000     128.5    P2p Pre-STD 
Gi1/0/6          Desg FWD 20000     128.6    P2p Pre-STD 
Gi1/0/7          Desg FWD 20000     128.7    P2p Pre-STD 
Gi1/0/8          Desg FWD 20000     128.8    P2p Pre-STD 
Gi1/0/9          Desg FWD 20000     128.9    P2p Pre-STD 
Gi1/0/13         Desg FWD 20000     128.13   P2p Pre-STD 
Gi1/0/14         Desg FWD 20000     128.14   P2p Pre-STD 
Gi1/0/15         Desg FWD 20000     128.15   P2p Pre-STD 
Gi1/0/16         Desg FWD 20000     128.16   P2p Pre-STD 
Gi1/0/17         Desg FWD 20000     128.17   P2p Pre-STD 
Gi1/0/18         Desg FWD 20000     128.18   P2p Pre-STD 
Gi1/0/19         Desg FWD 20000     128.19   P2p Pre-STD 
Gi1/0/20         Desg FWD 20000     128.20   P2p Pre-STD 
Gi1/0/21         Desg FWD 20000     128.21   P2p Pre-STD 
Gi1/0/22         Desg FWD 20000     128.22   P2p Pre-STD 
Gi1/0/23         Desg FWD 20000     128.23   P2p Pre-STD 
Gi1/0/29         Desg FWD 20000     128.29   P2p Pre-STD 
Gi1/0/32         Desg FWD 20000     128.32   P2p Pre-STD-Cf 
Gi1/0/33         Desg FWD 20000     128.33   P2p Edge Pre-STD-Cf 
Gi1/0/36         Desg FWD 20000     128.36   P2p 
Gi1/0/38         Desg FWD 20000     128.38   P2p Pre-STD-Cf 
Te1/1/1          Desg FWD 2000      128.53   P2p 
Gi2/0/1          Desg FWD 20000     128.55   P2p 
Gi2/0/2          Desg FWD 20000     128.56   P2p Pre-STD 
Gi2/0/3          Desg FWD 20000     128.57   P2p Pre-STD 
Gi2/0/4          Desg FWD 20000     128.58   P2p Pre-STD 
Gi2/0/5          Desg FWD 20000     128.59   P2p Pre-STD 
Gi2/0/6          Desg FWD 20000     128.60   P2p Pre-STD 
Gi2/0/7          Desg FWD 20000     128.61   P2p Pre-STD 
Gi2/0/8          Desg FWD 20000     128.62   P2p Pre-STD 
Gi2/0/9          Desg FWD 20000     128.63   P2p Pre-STD 
Gi2/0/13         Desg FWD 20000     128.67   P2p Pre-STD 
Gi2/0/14         Desg FWD 20000     128.68   P2p Pre-STD 
Gi2/0/15         Desg FWD 20000     128.69   P2p Pre-STD 
Gi2/0/16         Desg FWD 20000     128.70   P2p Pre-STD 
Gi2/0/18         Desg FWD 20000     128.72   P2p Pre-STD 
Gi2/0/19         Desg FWD 20000     128.73   P2p Pre-STD 
Gi2/0/20         Desg FWD 20000     128.74   P2p Pre-STD 
Gi2/0/21         Desg FWD 20000     128.75   P2p Pre-STD 
Gi2/0/22         Desg FWD 20000     128.76   P2p Pre-STD 
Gi2/0/23         Desg FWD 20000     128.77   P2p Pre-STD 
Gi2/0/24         Desg FWD 20000     128.78   P2p Pre-STD 
Gi2/0/25         Desg FWD 20000     128.79   P2p Pre-STD 
Gi2/0/31         Desg FWD 200000    128.85   P2p Pre-STD-Cf 
Gi2/1/1          Desg FWD 20000     128.103  P2p 

##### MST2    vlans mapped:   101,1210,1220-1223,1230,1240,1250
Bridge        address 44d3.ca5b.e600  priority      28674 (28672 sysid 2)
Root          this switch for MST2

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/0/1          Desg FWD 20000     128.1    P2p 
Gi1/0/2          Desg FWD 20000     128.2    P2p Pre-STD 
Gi1/0/3          Desg FWD 20000     128.3    P2p Pre-STD 
Gi1/0/4          Desg FWD 20000     128.4    P2p Pre-STD 
Gi1/0/5          Desg FWD 20000     128.5    P2p Pre-STD 
Gi1/0/6          Desg FWD 20000     128.6    P2p Pre-STD 
Gi1/0/7          Desg FWD 20000     128.7    P2p Pre-STD 
Gi1/0/8          Desg FWD 20000     128.8    P2p Pre-STD 
Gi1/0/9          Desg FWD 20000     128.9    P2p Pre-STD 
Gi1/0/13         Desg FWD 20000     128.13   P2p Pre-STD 
Gi1/0/14         Desg FWD 20000     128.14   P2p Pre-STD 
Gi1/0/15         Desg FWD 20000     128.15   P2p Pre-STD 
Gi1/0/16         Desg FWD 20000     128.16   P2p Pre-STD 
Gi1/0/17         Desg FWD 20000     128.17   P2p Pre-STD 
Gi1/0/18         Desg FWD 20000     128.18   P2p Pre-STD 
Gi1/0/19         Desg FWD 20000     128.19   P2p Pre-STD 
Gi1/0/20         Desg FWD 20000     128.20   P2p Pre-STD 
Gi1/0/21         Desg FWD 20000     128.21   P2p Pre-STD 
Gi1/0/22         Desg FWD 20000     128.22   P2p Pre-STD 
Gi1/0/23         Desg FWD 20000     128.23   P2p Pre-STD 
Gi1/0/29         Desg FWD 20000     128.29   P2p Pre-STD 
Gi1/0/32         Desg FWD 20000     128.32   P2p Pre-STD-Cf 
Gi1/0/36         Desg FWD 20000     128.36   P2p 
Gi1/0/38         Desg FWD 20000     128.38   P2p Pre-STD-Cf 
Gi1/0/42         Desg FWD 20000     128.42   P2p Pre-STD-Cf 
Te1/1/1          Desg FWD 2000      128.53   P2p 
Gi2/0/1          Desg FWD 20000     128.55   P2p 
Gi2/0/2          Desg FWD 20000     128.56   P2p Pre-STD 
Gi2/0/3          Desg FWD 20000     128.57   P2p Pre-STD 
Gi2/0/4          Desg FWD 20000     128.58   P2p Pre-STD 
Gi2/0/5          Desg FWD 20000     128.59   P2p Pre-STD 
Gi2/0/6          Desg FWD 20000     128.60   P2p Pre-STD 
Gi2/0/7          Desg FWD 20000     128.61   P2p Pre-STD 
Gi2/0/8          Desg FWD 20000     128.62   P2p Pre-STD 
Gi2/0/9          Desg FWD 20000     128.63   P2p Pre-STD 
Gi2/0/13         Desg FWD 20000     128.67   P2p Pre-STD 
Gi2/0/14         Desg FWD 20000     128.68   P2p Pre-STD 
Gi2/0/15         Desg FWD 20000     128.69   P2p Pre-STD 
Gi2/0/16         Desg FWD 20000     128.70   P2p Pre-STD 
Gi2/0/18         Desg FWD 20000     128.72   P2p Pre-STD 
Gi2/0/19         Desg FWD 20000     128.73   P2p Pre-STD 
Gi2/0/20         Desg FWD 20000     128.74   P2p Pre-STD 
Gi2/0/21         Desg FWD 20000     128.75   P2p Pre-STD 
Gi2/0/22         Desg FWD 20000     128.76   P2p Pre-STD 
Gi2/0/23         Desg FWD 20000     128.77   P2p Pre-STD 
Gi2/0/24         Desg FWD 20000     128.78   P2p Pre-STD 
Gi2/0/25         Desg FWD 20000     128.79   P2p Pre-STD 
Gi2/0/31         Desg FWD 200000    128.85   P2p Pre-STD-Cf 
Gi2/1/1          Desg FWD 20000     128.103  P2p

 

0 Helpful

AndreK
Beginner
Beginner
In response to balaji.bandi

‎09-30-2020 02:32 PM

Port configuration between switches.

Level 1

interface GigabitEthernet2/1/1
 description UP-F
 switchport trunk encapsulation dot1q
 switchport mode trunk
 storm-control broadcast level bps 10m
 storm-control multicast level bps 10m
 spanning-tree guard root
end

Level 2

interface GigabitEthernet1/0/1
 description KV04
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1-199,201-4094
 switchport mode trunk
 switchport nonegotiate
 ip dhcp snooping trust
end
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