WISM Deployment

[john smith]

Dear all

i hope your doing well,

i have a university project for unified wireless network deployment

there i have two 6500 series two core switches

i have four wism card to install in that chassies and have 800 ap of 1242 series

actually i did wlan setup before but just used only one controller but it is something bigger than that all i did before

and i have to configure redundency for all wisms

now i am wonder that what i ll do to build proper setup for that wlan

as i know i need 8 subnets for per wism 2 for management and 8 for ap manager as well.

and the configuration will be same on all wisms as per i ll configure on one controller in one wism.

for the redundency for sure i have four controllers on each chassis i will let joine half amount of ap to one wism and other half to another wism.

but for redundency what is best practice to do for?? should i have to let join some aps to one and the some to second and the some to third vice versa.

or there is any other technice to do that please help me on this this is very urgent for me because i have to start implementation the next coming week.

OR if any one has any kind of documentation that will help me to do that in easy steps please share with me?

i will be very thankfull to you for your help.

[Leo Laohoo]

there i have two 6500 series two core switches

Sorry but this confuses me.  Are the 6500 acting as core switches?

In your situation, there's alot of combination.  800 APs mean that you really need around 3 WiSMs and you can have an entire WiSM as a backup.

The question is HOW to deploy the WiSM.  Here's the argument:

1.  If you, say, put three WiSM in 6500-1 and you put one WiSM in 6500-2 and 6500-1 dies then you are royally s_crewed because only 300 APs will be serviced;

2.  If you put two WiSM in each and one of them failed, then you are still in the same situation as #1:  royally ... y'know the term. 

Whatever combo's you've deployed four WiSMs you're only prepared if an entire WiSM blade fails.  Your redundancy doesn't include a complete chassis failure.

To have full redundancy in a complete chassis failure then you need to have four primary APs in 6500-1 and another four blades as backup in 6500-2.  It would be nice if you have an etherchannel of 10Gb between the two 6500 chassis.

for the redundency for sure i have four controllers on each chassis i will let joine half amount of ap to one wism and other half to another wism.

Try to avoid inter-controller roaming.  This feature is not yet being perfected.  Sometimes it works but for some latency-critical applications it's not good enough yet.

but for redundency what is best practice to do for?? should i have to let join some aps to one and the some to second and the some to third vice versa.

Unless you have VSS, I'd recommend you put all APs in 6500-1 and use 6500-2 as a backup.

[john smith]

Thanks for your reply Leolaohoo

yes the two 6500 series switches act as core switchs and there is redundancy between them with VSS link.

the amount of the APs are 800 but still i will use approximately 550 to 580 only and the rest of the others either i will use them for an other branch or in future

so than 2 wisms cards on each chassis are perfet for all those APs

yes i agree with you to use 2 wisms on each chassis like 6500-1 primary  and 6500-2 secondry and put all aps in primary wisms on 6500-1 and also put them in other 6500-2 secondry for back up, once the primary core or the wisms are in this chassis will be fail or down than auto matically the APs will associate to the other chassis's wisms.

but here i have small confusion that if only one wism will fail on primary than what about only one will get active from the secondry one?

but the most confuseable question is that how i ll configure the wism cards for this type of enviorment i mean like redundany between the wisms?

have you any kind of doc. that could help me to configure my wisms for redundancy please share with me??

your reply will be very appreciated.

[Leo Laohoo]

so than 2 wisms cards on each chassis are perfet for all those APs

If I had a network like this, then I'd still consider <580 APs as "cutting it too close".  I'd prepare a third WiSM on one chassis and a total of three WiSM on 6500-2.

yes i agree with you to use 2 wisms on each chassis like 6500-1 primary  and 6500-2 secondry and put all aps in primary wisms on 6500-1 and also put them in other 6500-2 secondry for back up, once the primary core or the wisms are in this chassis will be fail or down than auto matically the APs will associate to the other chassis's wisms.

But what happens if your entire chassis goes down?  In this particular situation, there is no clear-cut answer.  There are a number of good bar-fight arguments here.  For example, management might be amicable for an entire blade failure but due to some constraints, like budget, they are willing to "look the other way" in case a chassis failure should happen (knock on wood).

but here i have small confusion that if only one wism will fail on primary than what about only one will get active from the secondry one?

Dude, that easy!  Before I answer your question, I'm going to give you a "disclaimer".  I am very happy to talk to you about this if your firmware is the latest 4.X and 6.X or any in the 7.X.  I won't discuss anything in the 5.X range because it's a waste of time as I've already pulled all of my hair out.

Here goes.  Cisco firmwares have a feature called "High Availability".  They can be configured in several ways:  the traditional CLI, per AP or globally.  Basically you can "tell" the AP that "in case there's a failure of the primary controller, go to the secondary.  If the secondary and primary controller fails, go to the tertiary controller.  If the primary or secondary controller recovers and you are the tertiary controller, swing across."

Configuring Backup Controllers

[john smith]

thanks for reply Leolaohoo

i got your idea but i still did not finaly understand that how i will done that job.

what ever it is as i told u already that i have 4 wisms and have 2 6500 series core with vss redundency between them and i have approximately 550 APs

just plz send me your opinion that what is the best practice to do this job complete

write in simple detail that how i have to distribute them in cores and how i have to configure the wisms for APs??

your reply will be very appreciated.

[Leo Laohoo]

Check the HTML link I've posted above.