Archive for the ‘Q&A’ Category

Q&A – VSS and Jumbo Frames

Tuesday, April 28th, 2009


I currently have a new blade chassis connected to my Nexus 5020 which has a Mulitchassis Etherchannel to a pair of 6509s running VSS. The blade system is using HP Flex 10 cards*. My first issue that I ran into was that I had to enable Jumbo MTUs on the Nexus. The reason being is the HP Flex 10 cards where sending jumbo frames which were getting dropped 🙁 I also had to enable Jumbo Frames on the the trunk ports as well as the ethernet ports on the VSS that connect back to the Nexus since there will be some inter-vlan routing going on. I guess I should enable jumbomtu on the layer 3 interfaces as well now that I think about it.

Do I also need to enable system jumbomtu on the VSS? What about the VSL links? The reason I ask is that when I run the command “show interface counter errors” I see giant frame errors on the VSL links as well as FCS errors. However, I cannot adjust the MTU size on the VSL links or the port channels since they are not switchports. Can I make the VSL links switchports or will VSS not allow this? I guess I’m a bit confused on the whole jumbomtu thing. Once you start to enable it where do you stop.

Thanks for the help,


Q&A – What do I need for CCNP lab?

Saturday, February 21st, 2009


I am currently working on my CCNA (ICDN2 test in 1 week!) and wish to
move to the CCNP track.

I really need help with the lab! I have done due diligence by
researching but just ended up more confused: I have been Googling for
the past 3 days.

I do not want to cut many corners on the lab. I have a reasonable
amount of cash to spend (up to $1000 is my target) and my lab has a
good start already.

Currently my lab looks like this:

2651 < -----I plan to convert this to an access server with 16 port (2 x8)octal using the correct NM module. 3640, 2 FE NM, 1 CSU/DSU #Switches 2960G 2950 (2) #Misc Aironet Access point 1100 Pix 506E 20U rack Thanks in advance. Charles


Q&A – Dial Plans

Sunday, October 19th, 2008

Hi Ted,

We are in the process of rolling out call manager 6 cluster in Europe. Currently We have call manager 5 Cluster in NA.

1) Inherited the system. ( It has 4 digit dial plan which will be starting to overlap soon)

2) We have inter cluster trunk setup ( no gate keeper)

3) VOIP will be deployed in France, UK, Romania, Germany Sweden and more….
a) since these countries use different dial plans ( Dial different length of digits , Emergency services etc…
b) Possible integration into a Avaya and CME deployment)

What is the best dial plan for this situation?

Currently the Consultant has recommended 5 digit dial plan?

1) What about site codes? for each country or office location?

How do get out of this mess…. I scoured the net and found no real world examples. I have ready the SRND but I am still lost. I have searched the Cisco net forms also.

Many Thanks in advance.



Q&A: Gearing-up for the new CCNA

Tuesday, July 31st, 2007



I saw your site and I’m hoping you can help. I took the CCNA exam for the first time late last month and again last week. I feel that I understand everything well enough to have passed the previous exam, but I’m a little lost with the new emphasis on security, etc. I would like to get certified ASAP, but don’t know if there is anyone with updated material yet. Do you know of a good source of information on security that would be relevant for what Cisco is testing on?