VX9000 total wireless LANs ?

  • 0
  • 2
  • Problem
  • Updated 8 months ago
  • Solved
Hi guys,

Bonjour,

Please help me that,  in VX9000 total of how many WLANs can able to add .?
Photo of Vimalraj Veerabathiran

Vimalraj Veerabathiran

  • 418 Points 250 badge 2x thumb
  • thankful

Posted 8 months ago

  • 0
  • 2
Photo of Shay Weir

Shay Weir

  • 1,648 Points 1k badge 2x thumb
From a management perspective, no more than 6 WLANs.  This will keep the beacons down to a low roar for better performance.
Hi Shay,

I'm using the same for different locations all-round India more than 150+ now. Would wants to know that for VX9000 what is maximum capacity we may add.

Likewise RFS4000 has only limited of 256WLANs.

Please help me,

Photo of Shay Weir

Shay Weir

  • 1,648 Points 1k badge 2x thumb
Yes.  You can have many WLANs configured.  The limitation of 6 is on the AP side itself.  There is the confusion.  Controller wise the numbers are as has been stated for the WLANs.  Just do not put more than 6 on each AP.  If you can standardize across your environment, that will hep with making changes in the future.  Change one, they all change.  You can also use wlan-overrides to customize each location.

Hope this helps to clarify the limit of 6 WLANs - per/AP not controller.
Thanks for your clear clarification Shay Weir.

If I'm using 9 SSID which all are in  hidden mode on same access Point over a corporate setup total of 53 Access points I'm using it.

It will cause any impact. If yes means please help me to sort it out.

FYI.
Access Point model :-  AP7532
Controller :-- VX9000
Photo of Christoph S.

Christoph S., Employee

  • 2,764 Points 2k badge 2x thumb
Hello Vimalraj,

If you're asking about the scalability of the VX9000 then the total number of WLANs/device would be 1022 taking into consideration the min hardware resources that should be allocated:

3 x VCPUs @ 2.4GHz
5GB RAM
5GB HDD
(Edited)
Photo of Ondrej Lepa

Ondrej Lepa, Employee

  • 5,116 Points 5k badge 2x thumb
Hello Vimalraj,

As per data sheet the limitation is 1,022 WLAN entries.
This is code limitation as VX does not broadcast WLAN at all.

Theoretical maximum of WLANs per AP is 32 (in configuration), with maximum of 8 SSID per radio (broadcasted).
However, you shall not exceed 6 WLANs per radio as written by Shay above.
Even 6 is very high number which will cause significant degradation of radio performance.
See this SSID Overhead Calculator by Revolution WiFi

Rule of thumb - do not use more than you need and try to aggregate wherever you can.

Regards,
Ondrej
Thanks a lot Ondrej,
Thanks for your clear clarification Ondrej,

If I'm using 9 SSID which all are in  hidden mode on same access Point over a corporate setup total of 53 Access points I'm using it.

It will cause any impact. If yes means please help me to sort it out.

FYI.
Access Point model :-  AP7532
Controller :-- VX9000
Photo of Ondrej Lepa

Ondrej Lepa, Employee

  • 5,116 Points 5k badge 2x thumb
Hi Vimalraj,

what do you mean by "hidden"?
Is it no broadcast-ssid or no answer-broadcast-probes?

  • no broadcast-ssid just leaves the SSID field empty, but beacon still has to occur due TIM etc.
  • no answer-broadcast-probes is mitigating active scanning with null SSID / blank request but will still respond to direct probe request.

These options won't help to relieve the utilization.
Based on the capacity planning and number of clients you may, or may not, experience issues with the radio performance.

In other words:

If you do not experience any issues so far, you probably did not exceed the capacity.
If you do experience client stability issues this is the point whee I would start considering wireless site survey / check the capacity planning.

Regards,
Ondrej
Photo of Shay Weir

Shay Weir

  • 1,648 Points 1k badge 2x thumb
When running that many SSIDs on a single AP (x53) the management traffic alone will kill performance.  Several things to consider.  Lowest data rates.  Set them to only connect at nothing lower than 9MB, best would be 18 or 24MB data rate.  This will force all to connect at higher rates, this leaving ample room for traffic.  AP management traffic will also use the higher rates to pass traffice to the RF-Domain.  This is good for the 2.4GHz radio.  For those on 5GHz, you should be okay to leave at default.

When you do not broadcast the SSID, each AP has to ask every AP what they have to offer.  Again, this creates more non data overhead.  Best to go ahead and broadcast the SSID.  Hacker can find even if not broadcast if that is what you are worried about.  Just be sure to enable strong security measures on each.

To help reduce the number of SSIDs, try using dynamic vlan assignments.  This works with your AAA policy and RADIUS server.  This helped us out greatly to eliminate 4 SSIDs so far.  When issuing a "show wireless clients", add the column to also include the vlan.  Guest or freewifi, should still have its own SSID and routed directly out.  Other Corporate SSIDs, should roll into 1.  Legacy devices may need their own based on what type of authentication functions they can handle.

You will need to research each device type and their wireless capabilities to determine basic lowest rates (work to raise up to 24MB).

Research each device authentication capabilities to eliminate SSIDs and use dynamic vlan assignments using AAA policy and RADIUS.

Hope this helps.
(Edited)
Photo of Ondrej Lepa

Ondrej Lepa, Employee

  • 5,064 Points 5k badge 2x thumb
Shay,

I have to admit that using dynamic VLAN assignent + AAA sound like really elegant way to do the sorting!

Good job

Regards,
Ondrej
Photo of Ronald Dvorak

Ronald Dvorak, Embassador

  • 46,958 Points 20k badge 2x thumb
Here a matrix on how the number of SSID and MBR affects the util in the air.
So try to lower the number of SSIDs per radio and increase the MBR to decrease the util.

Photo of Shay Weir

Shay Weir

  • 1,648 Points 1k badge 2x thumb
Too many APs and too many SSIDs will cause performance issues if not tuned correctly.  It does not matter who the vendor is Extreme, WiNG, Cisco, Aruba, Aerohive...  If your wireless network is not configured correctly, there will be problems.  The best real advise is to work with your local Extreme WiNG SE to assist in tuning your environment to provide the best experience for your customers.

This is what they do for you.
Photo of Shay Weir

Shay Weir

  • 1,648 Points 1k badge 2x thumb
Here is the link to the actual SSID Overhead Calculator:
 http://bit.ly/wifissidoverhead 

Give it a spin....