Имеем следующую топологию:



C -CISCO3550,
D1,D2,D3- DES-3526.

Проблема в том , что по замыслу cisco должен стать root bridge, а линк 100м должен стать "alternate" для всех instance_id,но получается что на D3 "alternate" становится 1G линк между C и D3.Пробывал На D3 ставить "config stp mst_ports 25 instance_id х priority 96" даля всех instance_id картина не меняется.

Прошивка на всех 3526 5.01.B52.

Kонфигурация CISCO:

!
spanning-tree mode mst
spanning-tree extend system-id
!
spanning-tree mst configuration
name test
revision 777
instance 1 vlan 13, 55
instance 2 vlan 23, 57
!
spanning-tree mst 0 priority 4096
spanning-tree mst 1 priority 4096
spanning-tree mst 2 priority 4096
!
interface GigabitEthernet0/1
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,13,23,55,57
switchport mode trunk
no ip address
!
interface GigabitEthernet0/2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,13,23,55,57
switchport mode trunk
no ip address
!

Конфигурация D1:

# VLAN

disable asymmetric_vlan
config vlan default delete 1-26
config vlan default add tagged 25-26
config vlan default add untagged 1-24
config vlan default advertisement enable
create vlan VLAN13 tag 13
config vlan VLAN13 add tagged 25-26
config vlan VLAN13 advertisement disable
create vlan VLAN23 tag 23
config vlan VLAN23 add tagged 25-26
config vlan VLAN23 advertisement disable
create vlan VLAN55 tag 55
config vlan VLAN55 add tagged 25-26
config vlan VLAN55 advertisement disable
create vlan VLAN57 tag 57
config vlan VLAN57 add tagged 25-26
config vlan VLAN57 advertisement disable
disable gvrp
config gvrp 1-26 state disable ingress_checking enable acceptable_frame admit_all pvid 1

# STP

config stp version mstp
config stp maxage 20 maxhops 20 forwarddelay 15 txholdcount 6 fbpdu enable
config stp priority 32768 instance_id 0
create stp instance_id 1
config stp instance_id 1 add_vlan 13,55
config stp priority 32768 instance_id 1
create stp instance_id 2
config stp instance_id 2 add_vlan 23,57
config stp priority 32768 instance_id 2
config stp mst_config_id name test revision_level 777
enable stp
config stp ports 1-24 externalCost auto hellotime 2 edge false p2p auto state disable
config stp ports 1-26 fbpdu disable
config stp ports 1-26 restricted_role false
config stp ports 1-26 restricted_tcn false
config stp mst_ports 1-26 instance_id 0 internalCost auto priority 128
config stp ports 25-26 externalCost auto hellotime 2 edge false p2p auto state enable
config stp mst_ports 1-26 instance_id 1 internalCost auto priority 128
config stp mst_ports 1-26 instance_id 2 internalCost auto priority 128

Конфигурация D2:

# VLAN

disable asymmetric_vlan
config vlan default delete 1-26
config vlan default add tagged 1,25
config vlan default add untagged 2-24,26
config vlan default advertisement enable
create vlan VLAN13 tag 13
config vlan VLAN13 add tagged 1,25
config vlan VLAN13 advertisement disable
create vlan VLAN23 tag 23
config vlan VLAN23 add tagged 1,25
config vlan VLAN23 advertisement disable
create vlan VLAN55 tag 55
config vlan VLAN55 add tagged 1,25
config vlan VLAN55 advertisement disable
create vlan VLAN57 tag 57
config vlan VLAN57 add tagged 1,25
config vlan VLAN57 advertisement disable
disable gvrp
config gvrp 1-26 state disable ingress_checking enable acceptable_frame admit_all pvid 1

# STP

config stp version mstp
config stp maxage 20 maxhops 20 forwarddelay 15 txholdcount 6 fbpdu enable
config stp priority 32768 instance_id 0
create stp instance_id 1
config stp instance_id 1 add_vlan 13,55
config stp priority 32768 instance_id 1
create stp instance_id 2
config stp instance_id 2 add_vlan 23,57
config stp priority 32768 instance_id 2
config stp mst_config_id name test revision_level 777
enable stp
config stp ports 1,25 externalCost auto hellotime 2 edge false p2p auto state enable
config stp ports 1-26 fbpdu disable
config stp ports 1-26 restricted_role false
config stp ports 1-26 restricted_tcn false
config stp mst_ports 1-26 instance_id 0 internalCost auto priority 128
config stp ports 2-24,26 externalCost auto hellotime 2 edge false p2p auto state disable
config stp mst_ports 1-26 instance_id 1 internalCost auto priority 128
config stp mst_ports 1-26 instance_id 2 internalCost auto priority 128

Конфигурация D3:

# VLAN

disable asymmetric_vlan
config vlan default delete 1-26
config vlan default add tagged 1,25
config vlan default add untagged 2-24,26
config vlan default advertisement enable
create vlan VLAN13 tag 13
config vlan VLAN13 add tagged 1,25
config vlan VLAN13 advertisement disable
create vlan VLAN23 tag 23
config vlan VLAN23 add tagged 1,25
config vlan VLAN23 advertisement disable
create vlan VLAN55 tag 55
config vlan VLAN55 add tagged 1,25
config vlan VLAN55 advertisement disable
create vlan VLAN57 tag 57
config vlan VLAN57 add tagged 1,25
config vlan VLAN57 advertisement disable
disable gvrp
config gvrp 1-26 state disable ingress_checking enable acceptable_frame admit_all pvid 1

# STP

config stp version mstp
config stp maxage 20 maxhops 20 forwarddelay 15 txholdcount 6 fbpdu enable
config stp priority 32768 instance_id 0
create stp instance_id 1
config stp instance_id 1 add_vlan 13,55
config stp priority 32768 instance_id 1
create stp instance_id 2
config stp instance_id 2 add_vlan 23,57
config stp priority 32768 instance_id 2
config stp mst_config_id name test revision_level 777
enable stp
config stp ports 1,25 externalCost auto hellotime 2 edge false p2p auto state enable
config stp ports 1-26 fbpdu disable
config stp ports 1-26 restricted_role false
config stp ports 1-26 restricted_tcn false
config stp mst_ports 1-26 instance_id 0 internalCost auto priority 128
config stp ports 2-24,26 externalCost auto hellotime 2 edge false p2p auto state disable
config stp mst_ports 1-26 instance_id 1 internalCost auto priority 128
config stp mst_ports 1-26 instance_id 2 internalCost auto priority 128


D3:
DES-3526:admin#sh stp ports 1,25
Command: show stp ports 1,25

MSTP Port Information
----------------------
Port Index : 1 , Hello Time: 2 /2 , Port STP enabled
Restricted role : False , Restricted TCN : False
External PathCost : Auto/200000 , Edge Port : False/No , P2P : Auto /Yes
Port Forward BPDU : disabled
BPDU Type : RSTP

Msti Designated Bridge Internal PathCost Prio Status Role
----- ------------------ ----------------- ---- ----------- ----------
0 8000/001B11B5B92C 200000 128 Forwarding Root
1 8001/001B11B5B92C 200000 128 Forwarding Root
2 8002/001B11B5B92C 200000 128 Forwarding Root


MSTP Port Information
----------------------
Port Index : 25 , Hello Time: 2 /2 , Port STP enabled
Restricted role : False , Restricted TCN : False
External PathCost : Auto/20000 , Edge Port : False/No , P2P : Auto /Yes
Port Forward BPDU : disabled
BPDU Type : RSTP

Msti Designated Bridge Internal PathCost Prio Status Role
----- ------------------ ----------------- ---- ----------- ----------
0 3164/B80000000000 20000 128 Discarding Alternate
1 8001/00179ABCA6CA 20000 128 Discarding Alternate
2 8002/00179ABCA6CA 20000 128 Discarding Alternate

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