Ask the Expert: Implementing and Troubleshooting Virtual Switching System (VSS) on Cisco Catalyst Switches 4500 and 6500

[ciscomoderator]

Virtual Switching System (VSS) is network system virtualization technology that pools multiple Cisco Catalyst 6500 Series Switches into one virtual switch, increasing operational efficiency, boosting nonstop communications, and scaling system bandwidth capacity to 1.4 Tbps. At the initial phase, a VSS will allow two physical Cisco Catalyst 6500 Series Switches to operate as a single logical virtual switch called a virtual switching system 144. 
his session will provide an opportunity to learn and ask questions about how to implement, configure and troubleshoot VSS in Cisco Catalyst Switches 6500 and 4500.

Ask questions from Monday, September 7 to Friday, September 18, 2015

Featured Experts

InayathUlla Sharieff is a Customer support engineer in High-Touch Technical Services (HTTS) team supporting LAN Switching and Data center Products. His areas of expertise include Cisco Catalyst 2000,3000,4000 ,6500 and Cisco Nexus 7000 Switches. Shariff has over 8 years of industry experience working with large enterprise and Service Provider networks. He holds Bachelors in Computer Sciences degree and these Cisco  certifications: CCNA, CCNP (in Routing and Swtiching), and CCIE in R&S (# 43263). He is pursuing the CCIE in Data Centers.

Suresh  Vs is a Customer Support Engineer in High-Touch Technical Services (HTTS) at Cisco Bangalore, India. He has over 11 years of industry experience working with large Enterprise and Service Provider networks. He has been working with HTTS from past 4 years and supporting LAN Switching and Data center Products. His areas of expertise include Cisco Catalyst 2000, 3000, 4000, 6500 and Cisco Nexus 7000 Switches. Suresh holds a Bachelor's of Sciences in Electrical and Electronics Engineering from Madras University. He has these certifications: CCNA, CCNP, CCIE Data Center (# 46658).

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[Reza Sharifi]

Is the title supposed to be 6500 or 65000?

Reza

[Monica Lluis]

Thanks for the catch, Reza. Indeed it is 6500... ;-)

Monica

[Monica Lluis]

I fixed the title.

[Murugan Pambulu]

do we need to have same kind of chassis to do VSS ?

[InayathUlla Sharieff]

Murugan,

Yes the chassis needs to be same.

Regards

Inayath

[InayathUlla Sharieff]

Virtual Switching System (VSS) is a method to combine two physical switches into one logical switch to achieve physical redundancy, Spanning-Tree blocking elimination, and increased bandwidth. VSS was first available in Cisco 6500 but it has recently been introduced to Cisco 4500 and 4500X. This article provides configuration that will allow you to easily enable VSS on these switches.

VSS on Cisco 6500

Requirements

• Virtual Switching Supervisor 720-10GE (VS-S720-10GE-3C and VS-S720-10GE-3CXL) with IOS 12.2(33)SXH1 and IP Base
• or Supervisor 2T (VS-S2T-10G and VS-S2T-10G-XL) with IOS 12.2(50) SY and IP Base

Cabling Between Chassis

• Minimum of two 10Gbps links with at least one on the Supervisor
• Minimum of one (more is recommended) 1Gbps or 10Gbps links for dual-active detection 

VSS on Cisco 4500/4500X

Requirements

• Supervisor Engine 7-E (WS-X45-Sup7-E) (IP Base)
• Or Supervisor Engine 7L-E (WS-X45-Sup7L-E) (Enterprise Services)
• Or 4500X Switch Family (IP Base)
• Minimum IOS XE 3.4.xSG
• IOS XE 3.5.0E for L3 MEC and Fast Hello Dual-Active Detection support (Recommended)

Cabling Between Chassis

• Minimum of two 10Gbps links with at least one on the Supervisor (4500 Only)
• Minimum of one (more is recommended) 1Gbps or 10Gbps links for dual-active detection 

HTH

Regards

Inayath

[shoaib sheikh]

Hello Inayat/Suresh,

Let me know if it possible what I have asked in the link below:

https://supportforums.cisco.com/discussion/12590776/vss-failover-without-powering

I have done same thing in ASA in failover mode where you just have to remove one ASA from network and other will takeover as active. The difference is here two ASA have two different IP's but in VSS we have only one IP of both chassis.

[InayathUlla Sharieff]

Shoaib,

I went through your post and I see that its working as expected.

Below is the link which explains in details about what you are looking for:-

http://www.cisco.com/c/en/us/products/collateral/switches/mgx-8800-series-switches/white_paper_c11-729039.html

In case if still this doesnt solve your query do let us know and we will get back to you with the answer.

Regards

Inayath

[Raja_D]

Hi Sharieef,

Does the 2 individual vss switches have to be configured with ip addresses while having both of those identified by one single logical switch ip ? if the 2 vss switches are configured with ip address individually, how to check the ip addresses of both switches when logged into the switch. please share the commands relating to the same.

[Suresh Vinayagam Subramanian]

Hello Raj,

A VSS combines a pair of Catalyst 6500 series switches into a single network element. The VSS manages the redundant links, which externally act as a single port channel.

The VSS simplifies network configuration and operation by reducing the number of Layer 3 routing neighbors and by providing a loop-free Layer 2 topology.

One active supervisor in each chassis with inter-chassis StatefulSwitchover (SSO)
Active supervisor manages the control plane functionssuch as protocols (routing, EtherChannel, SNMP, telnet, etc.) and hardware control (Online Insertion Removal, port management)

For example , For simplicity, let us say  we have 1 supervisor and 4 linecards in one switch and another switch has 1 supervisor and 6 linecards then it will like one big switch have 2 supervisor and 10 linecards.

switch 1 = 1 sup + 4 linecards 

switch 2 = 1 sup + 6 linecards

 VSS = 2 sup + 10 linecards.

So you can execute all the command which you execute in standalone switch . Expect few vss commands.

show switch virtual  ---> shows vss domin id and virtual switch active/standby details

sh mod switch all   ---> shows both switch module details

sh ip int brief  ---> shows both switch interface status. 

you can find more details in below link.

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/vss.html

HTH
Regards,
VS.Suresh.

show run  -----> you will see whole switch configuration .

[Raja_D]

Thanks for the information Suresh.

so the chassis with lower priority will be the Active and one with higher will be standby. right ?

[Suresh Vinayagam Subramanian]

Hello Raj,

Yes,your understanding is correct but highest priority switch will becomes active.

If you boot both chassis simultaneously, the VSL ports become VSS active, and the chassis will come up as VSS active and VSS standby. If priority is configured, the higher priority switch becomes active.

HTH
Regards,
VS.Suresh.

[Raja_D]

Dear Suresh,

This is the output that was taken from a VSS configured switch WS-C4500X-32.

Switch  Switch Status  Preempt       Priority  Role     Local   Remote
        Number         Oper(Conf)    Oper(Conf)         SID     SID
--------------------------------------------------------------------
LOCAL   1      UP      FALSE(N )     110(110)  STANDBY  0       0
REMOTE  2      UP      FALSE(N )     100(100)  ACTIVE   8388    6016

show switch virtual redundancy

Executing the command on VSS member switch role = VSS Active, id = 2

                  My Switch Id = 2
                Peer Switch Id = 1
        Last switchover reason = none
    Configured Redundancy Mode = Stateful Switchover
     Operating Redundancy Mode = Stateful Switchover

configuration info

switch virtual domain 20
 switch mode virtual
 switch 1 priority 110
 mac-address use-virtual
 

I notice from above output that the switch shows local with priority as 110 and it shows as standby and the other with priority 100 active. Kindly clarify

[Suresh Vinayagam Subramanian]

Hi Raj,

That switch might have booted before other switch . Below is  the details.

System Initialization :

If you boot both chassis simultaneously, the VSL ports become VSS active, and the chassis will come up as VSS active and VSS standby. If priority is configured, the higher priority switch becomes active.

If you boot up only one chassis, the VSL ports remain inactive, and the chassis comes up as VSS active. When you subsequently boot up the other chassis, the VSL links become active, and the new chassis comes up as VSS standby.

you can find more details in below link.

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/vss.html#wp1053927

HTH
Regards,
VS.Suresh.