VSS and vPC

There are several good documents and blogs about the VSS and vPC. Here are a few:

http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-6500-series-switches/white_paper_c11_589890.html

http://mycciedatacenter.blogspot.com/2013/06/vss-vs-vpc-difference-between-vss-and.html

Here are sample configuration:

6500_S1 & 6500_S2

! CONFIGURE THE FIRST SWITCH: 65K1

!create virtual domain

65K1(config)#switch virtual domain 1

65K1(config-vs-domain))#switch 1

65K1(config-vs-domain))#switch 1 priority 110

!configure virtual switch link (VSL)

65K1(config)#interface port-channel 1

65K1(config-if)#switchport

65K1(config-if)#switch virtual link 1

65K1(config-if)#no shut

65K1(config-if)#interface range te1/1 – 2

65K1(config-if-range)#switchport

65K1(config-if-range)#switchport mode trunk

65K1(config-if-range)#switchport nonegotiate

65K1(config-if-range)#channel-group 1 mode on

65K1(config-if-range)#no shut

65K1(config-if-range)#end

!enable dual active detection – use fast-hello in this case

65K1(config)#interface te1/ 3

65K1(config-if)#no switchport

65K1(config-if)#no shut

65K1(config-if)#dual-active fast-hello

!turn on vss

65K1#switch convert mode virtual

! CONFIGURE THE FIRST SWITCH: 65K2

!create virtual domain

65K2(config)#switch virtual domain 1

65K2(config-vs-domain))#switch 1

65K2(config-vs-domain))#switch 1 priority 110

!configure virtual switch link (VSL)

65K2(config)#interface port-channel 2

65K2(config-if)#switchport

65K2(config-if)#switch virtual link 2

65K2(config-if)#no shut

65K2(config-if)#interface range te1/1 – 2

65K2(config-if-range)#switchport

65K2(config-if-range)#switchport mode trunk

65K2(config-if-range)#switchport nonegotiate

65K2(config-if-range)#channel-group 1 mode on

65K2(config-if-range)#no shut

65K2(config-if-range)#end

!enable dual active detection – use fast-hello in this case

65K2(config)#interface te1/ 3

65K2(config-if)#no switchport

65K2(config-if)#no shut

65K2(config-if)#dual-active fast-hello

!turn on vss

65K2#switch convert mode virtual

!verifying the VSS

65K1#show etherc sum

65K1#show switch virtual

65K1#show switch virtual role

65K1#show switch virtual link

N7K1 & N7K2

! CONFIGURE THE FIRST SWITCH: N7K1

!enable vpc feature and create vpc domain

N7K1(config)# feature vpc

N7K1(config)# vpc domain 1

! first, create a vrf

N7K1(config)#vrf context Keepalive

! create peer keep alive link (layer 3)

N7K1(config)#interface Ethernet 1/1

N7K1(config-if)#no switchport

N7K1(config-if)#ip address 10.1.1.11 255.255.255.0

N7K1(config-if)#vrf member Keepalive

N7K1(config-if)#no shut

N7K1(config-if)#vpc domain 1

N7K1(config-vpc-domain)# peer-keepalive destination 10.1.1.12 source 10.1.1.11 vrf Keepalive

N7K1(config-vpc-domain)#role priority 1

! configure vpc peer link

N7K1(config)#int Ethernet 1/ 2 – 3

N7K1(config-if-range)#switchport

N7K1(config-if-range)#switchport mode trunk

N7K1(config-if-range)#switch trunk allowed vlan all

N7K1(config-if-range)#switchport trunk native vlan 5

N7K1(config-if-range)#spanning-tree port type network

N7K1(config-if-range)#channel-group 1

N7K1(config-if-range)# interface port-channel 1

N7K1(config-if)# vpc peer-link

! config the vpc for a server with dual nic

N7K1(config)#int interface Ethernet 1/ 4

N7K1(config-if)# description SQL_Server1_Nic_1

N7K1(config-if)#switchport

N7K1(config-if)#switchport access vlan 5

N7K1(config-if)#spanning-tree port type edge

N7K1(config-if)#channel-group 51 mode active

N7K1(config-if)#no shut

N7K1(config-if)#interface port-channel 51

N7K1(config-if)#vpc 51

! CONFIGURE THE SECOND SWITCH: N7K2

! enable vpc feature and create vpc domain

N7K2(config)# feature vpc

N7K2(config)# vpc domain 1

! first, create a vrf

N7K2(config)#vrf context Keepalive

! create peer keep alive link (layer 3)

N7K2(config)#interface Ethernet 1/1

N7K2(config-if)#no switchport

N7K2(config-if)#ip address 10.1.1.12 255.255.255.0

N7K2(config-if)#vrf member Keepalive

N7K2(config-if)#no shut

N7K2(config-if)#vpc domain 1

N7K2(config-vpc-domain)# peer-keepalive destination 10.1.1.11 source 10.1.1.12 vrf Keepalive

N7K2(config-vpc-domain)#role priority 2

! configure vpc peer link

N7K2(config)#int Ethernet 1/ 2 – 3

N7K2(config-if-range)#switchport

N7K2(config-if-range)#switchport mode trunk

N7K2(config-if-range)#switch trunk allowed vlan all

N7K2(config-if-range)#switchport trunk native vlan 5

N7K2(config-if-range)#spanning-tree port type network

N7K2(config-if-range)#channel-group 1

N7K2(config-if-range)# interface port-channel 1

N7K2(config-if)# vpc peer-link

! config the vpc for a server with dual nic

N7K2(config)#int interface Ethernet 1/ 4

N7K2(config-if)# description SQL_Server1_Nic_2

N7K2(config-if)#switchport

N7K2(config-if)#switchport access vlan 5

N7K2(config-if)#spanning-tree port type edge

N7K2(config-if)#channel-group 51 mode active

N7K2(config-if)#no shut

N7K2(config-if)#interface port-channel 51

N7K2(config-if)#vpc 51

! verifying the vpcs

N7K1# show vpc brief

N7K1# show vpc consistency-parameters vpc 51

N7K1# show vpc consistency-parameters global

EEM Applet

Our network monitoring program detected  ICMP latency from a few WS-C3560CG-8PC-S switches recently. The "show process cpu sort" shows normal output. However, the "show process cpu history" indicates CPU utilization was always 60% and spike over 90% from time to time. To capture which process is the culprit, Cisco recommended to use following EEM (Embedded Event Manager) applet:

event manager applet high-cpu

!

event snmp oid 1.3.6.1.4.1.9.9.109.1.1.1.1.3 get-type next entry-op gt entry-val 80 poll-interval 5 exit-time 500 maxrun 600

!

action 0.1 cli command "enable"

action 0.2 syslog msg "TAC - Capturing high cpu information to flash:"

action 0.3 cli command "term length 0"

action 1.1 cli command "show process cpu sorted | redirect flash:eem-cpu1.txt"

action 1.2 cli command "show interface | redirect flash:eem-interface1.txt"

action 1.3 cli command "show interface stats | redirect flash:eem-stat1.txt"

action 1.4 cli command "show ip traffic | redirect flash:eem-traffic1.txt"

action 2.1 cli command "show process cpu sorted | redirect flash:eem-cpu2.txt"

action 2.2 cli command "show interface | redirect flash:eem-interface2.txt"

action 2.3 cli command "show interface stats | redirect flash:eem-stat2.txt"

action 2.4 cli command "show ip traffic | redirect flash:eem-traffic2.txt"

What this applet will do is when CPU process is over 80%, it will write those show output to text files in flash. This applet did capture the "virtual exec" was running over 90% of CPU process. 

Just felt this is a cool utility to share. You can find more EEM samples here: http://www.cisco.com/en/US/docs/switches/datacenter/sw/5_x/nx-os/system_management/configuration/guide/sm_eem_events_and_examples.html

BTW, the root cause of the high CPU utilization is a bug in the IOS. Upgraded to c3560c405ex-universalk9-mz.122-55.EX3.bin seems bring down the utilization to 20%.