Advanced Traffic Management Guide K/KA/KB.15.15

MST Configuration Name : mstp-vrrp
MST Configuration Revision : 1
MST Configuration Digest : 0x1936FB656D900E359ED1D09A34AC0AAC
IST Mapped VLANs : 1
Instance ID Mapped VLANs
----------- ------------------------------------------------
1 3-5,23-25,33-35,43-45
2 7-9,27-29,37-39,47-49
Cisco 3550 (IDF2WEST)
Configure the switch name
>enable
#:configure terminal
(config)#: hostname IDF2WEST
(configures system name)
Configure VLANs on the switch
This switch will be configured with VLANs 1, 23, 24, 25, 27, 28, and 29. VLAN 1 will be untagged
on trunks and used only as a management VLAN. Set up a management IP on VLAN 1 and a
default gateway.
IDF2WEST(config)#: vlan 1
IDF2WEST(config-vlan)#: vlan 23-25,27-29
IDF2WEST(config-vlan)#: exit
IDF2WEST(config)#: interface vlan 1
IDF2WEST(config-if)#: ip address 10.1.1.29 255.255.255.0
IDF2WEST(config-if)#: exit
IDF2WEST(config)#: ip default-gateway 10.1.1.1
Configure dot1q trunking on the switch
To keep it simple in this design all edge switches are similarly configured. Most edge switches
connect to the 8200 on ports 47 and 48, and connect to the second switch in their IDF on ports
45 & 46. All links are configured as a “LAG” or “trunk-group”, meaning 2 links aggregated
together to provide link redundancy and improve bandwidth. Configure VLANs allowed on each
LAG and configure spanning tree cost. The 3550s are 10/100 switches so the default path cost
is 200000 for one 100M link. In order to block the correct port the cost needs to be configured
as 20000 on interface port-channel 1 which leads to the 8200A, and 20000 on interface
port-channel 2 which leads to IDF2EAST.
IDF2WEST(config)#: interface range fastethernet 0/47-48
IDF2WEST(config-if-range)#: channel-group 1 mode on
IDF2WEST(config-if-range)#: interface po 1
IDF2WEST(config-if-range)#: switchport trunk encapsulation dot1q
IDF2WEST(config-if-range)#: switchport mode trunk
IDF2WEST(config-if-range)#: switchport trunk allowed vlan 1,23-25,27-29
IDF2WEST(config-if-range)#: spanning-tree cost 20000
IDF2WEST(config-if-range)#: exit
IDF2WEST(config)#:interface range fastethernet 0/45-46
IDF2WEST(config-if-range)#: channel-group 2 mode on
IDF2WEST(config-if-range)#: interface po 2
IDF2WEST(config-if-range)#: switchport trunk encapsulation dot1q
IDF2WEST(config-if-range)#: switchport mode trunk
396 Spanning tree interoperability between HP and Cisco switches