Wireless Access

Hi All,

I need to upgrade the current wireless setup in my organization with L3 Mobility... Please refer below exciting wireless setup...

Controller 1 - 192.168.1.1 Master

Controller 2 - 192.168.1.2 Standby

VIP: 192.168.1.3

SSID – Corporate_Users - VLAN 10 IP Pool: 10.1.1.0/21

SSID – Guest_Users        - VLAN 20 IP Pool: 172.168.1.0/23

We are going to divide exicting building in 4 different zones... Each zones will lie under different VLAN, means separated at L3...

Also we need to enable L3 roaming… Please suggest the same, How can I configure L3 roaming in Master controller, as I have two Aruba controller configured in master standby mode… configuration of HA and FA… Suggest Mobility group, AP group… Please suggest with best practice…

All VLANs in the same building should have the same VLAN.  There is no advantage to having different VLANs depending on where you are in the building.  As a matter of fact it makes things more complicated, because you have to configure mobility between 4 controllers.  In addition it makes things more difficult to troubleshoot if users are roaming between controllers.  If you have a single controller serving a building, ALL users should have the same VLAN in the building...

Hi cjoshep,

Thanks for the reply...

But here is issue with huge broadcast domain... Actually as per the requirement, we are going completely devide the building in four different LAN, means completely L3 seperated Network... We are performing the same due to overcome with the STP loop... In this case our wireless network is also going to seperated at Layer 3...

As per the Aruba config guide, in this situation we have configure 4 Mobility controller per VLAN... One is master and others are Local and part of same Mobility Group...

My question is, Can we configure and enable L3 roaming on single Master controller in my case ?? How layer 3 roaming happen in thiscase ?? If yes, than provide me guidence and also share any document if possible...

You said "suggest best practice" in your first email.

Before I answer that, let me get an idea of your network:

How many access points, and how many controllers and what model?

Hi cjoshep,

Please find the below details

Total AP is around 500+

AP Model Aruba AP-225

Two Aruba 7210 Mobility controller, running in Master/Standby Mode

2 SSID (Corp and Guest)

1 AP Group

So the 7210 has a capacity of 512 access points, so just having two controllers will not get you where you want to go, because a backup master cannot terminate access points;  a backup master is just for failover.

Do you have other controllers besides these two, or you do not want N+1 redundancy?

With regards to the VLAN sizes, you can also do something called VLAN pooling, where you can pool a number of VLANs to add user capacity, so that users are load-balanced into VLANs, but they would maintain the same VLAN no matter where they are.  We also promote using single large VLANs, because with good broadcast suppression, size is not an issue:  http://community.arubanetworks.com/t5/Validated-Reference-Design/Single-VLAN-Architecture-for-WLAN/ta-p/257196