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What’s New on Cisco Catalyst 6500 Series? - FAQ from Live Webcast





With Richard Michael and Somu Jayaraman 

During the live event, Cisco subject matter experts Richard Michael and Somu Jayaraman focused on troubleshooting switching issues with the Cisco Catalyst 6500 and the architecture of the latest hardware in the Cisco Catalyst 6500 family series, Sup2T and 6800I. They will also cover common problems when migrating from Sup720 to Sup2T and introduce the latest troubleshooting tools for some common problems such as high CPU, Netflow issues, QoS, and CEF troubleshooting.

You can download the slides of the presentation in the attached document.

Richard Michael Michael is an engineer with technical services at the Cisco TAC center in Bangalore, India. He has approximately seven years of industry experience. Richard's areas of expertise include LAN switching and data center products such as Cisco Catalyst 6500, 4500, 3750, and 2960 and Cisco Nexus 7000, 5000, and 2000 Series Switches. His current responsibilities include working closely with the EMEA partners, service providers, and enterprise customers. Richard is also responsible for developing content for data center products both for internal and external use. He holds a degree in electronics from St. Joseph's College.

Somu Jayaraman is a customer support engineer with the Cisco TAC Center in Bangalore, India. He has six years of industry experience, and his areas of expertise include LAN routing and switching and data center technologies. Somu has been involved in various escalation requests from India, Singapore, and Australia and is currently working as a technical lead for the LAN switching team in Bangalore, India. He holds a degree in electronics and communication engineering from Anna University.


General Questions


Q. What is the Purpose of Access-List Entry (ACE) Counter?

A.  The ACE counter is used in order to maintain the Access-List (ACL) statistics.


Q. Is a 40-Gb module supported on a Supervisor Engine 2T (SUP2T), and what is the model number of the line card if it is?

A.  A. Yes. A 40-Gb module is supported on SUP2T, and the model number of the line card is WS-X6904-40G-2T. For more information about this, reference the Cisco article below.

40 Gigabit Ethernet on Cisco Catalyst 6500 Series Switches: How It Works


Q. What is SUP, and what is its role in the switch?

A.  The SUP, or Supervisor Engine, is basically the brain of the switch and is responsible for 12/13 packet forwarding.


Q. Do the Catalyst 6500 (CAT6k) Series Switches run Cisco CATOS or Cisco IOS®?

A.  The CAT6k Series Switches used to run Cisco CATOS, which is now unsupported. These switches now run Cisco IOS and IOS-XE.  


Q. Does the forwarding engine check the packet headers? 

A.  Yes. The packet headers are sent to the forwarding engine for decisions. 


Q. Do all of the line cards depend upon the SUP for decisions, and is the forwarding information distributed to all of the line cards?

A. The packet forwarding decision depends upon the type of ingress module in the switch. For modules with DFC, the decision is made on the line card itself.


Q. How do I set the console speed in ROMMON mode so that it corresponds to the higher-than-9600 baud in Cisco IOS?

A. In order to change the baud rate in the SUP2T, you must enter rommon>confreg mode. Once you are in this mode, you see these options: 

rommon 1 > confreg
 Configuration Summary :
 => console baud: 9600
 => autoboot from: autoboot disabled
do you wish to change the configuration? y/n  [n]:  ychange console baud rate? y/n  [n]:  y
enter rate:
0 = 9600
A: change console baud rate? y/n  [n]:  y
enter rate: 
0 = 9600,  1 = 4800,  2 = 1200,  3 = 2400 4 = 19200, 5 = 38400, 6 = 57600   [0]:  5


Q. Is a different type of cable needed in order to connect to CMP?

A. The CMP is a different processor and has its own bootflash/RAM. An Ethernet port is available on the front panel of the SUP.


Q. How do I block Layer 3 (L3) broadcasts from the CPU?

A. In order to block L3 broadcasts from the CPU, add a rate-limiter and Control Plane Policy (CoPP) to the switch. 


Q. What are the Packets Per Second (PPS) processing capabilities of SUP2T and Supervisor Engine 720 (SUP720)?

A. The PPS rate is in the millions. The PPS is a function of the packet size, which means smaller packets at the same line rate. 


Q. What fabric utilization value is considered normal?

A. The fabric utilization varies with the traffic pattern and services that run on the box. 


Q. Which line cards are supported on SUP2T?

A. Reference the Cisco Catalyst 6500 Series Supervisor Engine 2T Data Sheet for information about the line cards that are supported on the SUP2T.


Q. What is Embedded Logic Analyzer Module (ELAM)?

A. The ELAM is a tool that is used in order to find the hardware packet forwarding decision. 


Q. Is CoPP enabled by default on SUP2T?

A. Yes. CoPP is enabled by default. If there are any silent packet drops, you can check the CoPP with the show platform control-plane policy command. 


Q. Is DVIF grouped with the multicast group list?

A.  Reference the "Ask the Expert" discussion for more information.


Q. Are platform hardware rate-limiters enabled by default? 

A. Some rate-limiters are enabled by default, but not all. Enter the show platform rate-limit command in order to view the list of rate-limiters. 


Q.  When the master stack member resets, does the uplink ether channel reset or failover? 

A. Failover occurs quickly, and there is no network outage, even if the master stack member uplink ether channel goes down.


6800IA (Instant Access) and FEX related Questions


Q. Is there a release date for instant access that includes more than 21FEX, and does it require a new SUP or software update?

A. Support for 2000 access ports is targeted in Release 15.2(1)SY, which has an anticipated release date of December 2014. This is still in the testing phase, and details will be available in April 2014. The goal is to support 2000 ports with both SUP2T and 6880-X. 


Q. What are the differences between the 6500IA and Normal 6500?

A.  Reference the "Ask the Expert" discussion for more information. 


Q. Can a fabric path be built over the CAT6k Series Switch, or is a Cisco Nexus Series Switch required in order to integrate? 

A. You can build a fabric path over a CAT6k Series Switch, but the supervisor engine must be SUP2T with a 6800IA. The 6800I cannot work as a standalone switch.


Q. Is TRILL supported on the CAT6K Series switches?

A. The CAT6k SUP2T is not a TRILL-based platform, so it does not support fabric paths. However, the Cisco Nexus 7000 Series Switches use TRILL-based platforms, so they do support fabric paths.


Q. Where is the packet forwarding decision made when the packet must exit the IA switch?

A.  Reference the "Ask the Expert" discussion for more information.


Q. What is the maximum number of three-switch stacks that can be added to the CAT6K Series switch? 

A. You can add up to seven nodes, and each node carries three 6848 IA stack members.


Q. Is trust dscp/cos supported in IA Clients?

A. Only trust DSCP is currently supported by the ports. 


Q. What is the maximum number of queues supported on the 6848IA?

A. There are four queues in the 6848 platform: one is a priority queue, and the others are standard queues. The priority queue only carries control plain traffic, such as <expand this acronym> (BPDU). All of the standard queues are used for normal traffic.  


Q. Is the In-Service Software Upgrade (ISSU) feature supported on a CA T6K Series Switch with a 6848IA client?

A. Yes. The ISSU feature is supported on a 6848IA client and we can used during an IOS upgrade. 


Q. If there are two uplinks from the FEX to the CAT 6K, does the spanning tree block one of the ports? 

A. No. The uplink port will not be block and it is always in the forwarded state.


Webcast Related Links:

Community Member


Does Cisco Switches, like 6500 series, support TRILL configuration?