Wireless Access

HI Airheads,

i have a customer who has 6 x Aruba 7210 controllers 3 in DATA CENTRE cluster and 3 in DISASTER RECOVERY CENTRE (DRC).

They have 700 x AP'S spread across 3 x 7210 controllers in data centre and if data centre goes down the DRC cluster takes over.

This failover is achieved through use of LMS and Backup LMS in the AP system profile.

The failover works great and with a pre-emption set that works just great.

However...  customer has noticed that when they start to add more AP's (>700) they are not showing the the backup LMS (200 approx.)

I'm going to do some debug but jus thought i would ask the experts what they think of my configuration ?

i was hoping with a capacity of 3 x 512 AP's that i would be ok ?

cheers

Pete

-------------------------------------------

Clarify please?  I don't think you actually asked a question.

Best guess answer:  The Backup LMS is only ever used if none of the cluster nodes that are part of the LMS cluster are responding.  Your primary site has to be entirely offline for the AP to switch over, not just denying the AP a connection.

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Carson Hulcher, ACEX#110

Original Message:
Sent: Dec 15, 2025 04:22 AM
From: peter.elms
Subject: controller clustering with LMS backup LMS

HI Airheads,

i have a customer who has 6 x Aruba 7210 controllers 3 in DATA CENTRE cluster and 3 in DISASTER RECOVERY CENTRE (DRC).

They have 700 x AP'S spread across 3 x 7210 controllers in data centre and if data centre goes down the DRC cluster takes over.

This failover is achieved through use of LMS and Backup LMS in the AP system profile.

The failover works great and with a pre-emption set that works just great.

However...  customer has noticed that when they start to add more AP's (>700) they are not showing the the backup LMS (200 approx.)

I'm going to do some debug but jus thought i would ask the experts what they think of my configuration ?

i was hoping with a capacity of 3 x 512 AP's that i would be ok ?

cheers

Pete

-------------------------------------------

hi Carson,

thanks for getting back.

yes you're right my explanation is a bit ropey.

i now think i know what the issue is.

as discussed 3 x 7210's in Data Centre gives a capacity of 1536 x AP's except when the AP's are in a cluster

the quantity is halved.

So the customer is getting NO standby controller on AP's that are over and above this quantity (768 x AP's).

i think they will need extra controllers to facilitate their requirements.

regards

Pete

Clarify please?  I don't think you actually asked a question.

Best guess answer:  The Backup LMS is only ever used if none of the cluster nodes that are part of the LMS cluster are responding.  Your primary site has to be entirely offline for the AP to switch over, not just denying the AP a connection.

------------------------------
Carson Hulcher, ACEX#110

Original Message:
Sent: Dec 15, 2025 04:22 AM
From: peter.elms
Subject: controller clustering with LMS backup LMS

HI Airheads,

i have a customer who has 6 x Aruba 7210 controllers 3 in DATA CENTRE cluster and 3 in DISASTER RECOVERY CENTRE (DRC).

They have 700 x AP'S spread across 3 x 7210 controllers in data centre and if data centre goes down the DRC cluster takes over.

This failover is achieved through use of LMS and Backup LMS in the AP system profile.

The failover works great and with a pre-emption set that works just great.

However...  customer has noticed that when they start to add more AP's (>700) they are not showing the the backup LMS (200 approx.)

I'm going to do some debug but jus thought i would ask the experts what they think of my configuration ?

i was hoping with a capacity of 3 x 512 AP's that i would be ok ?

cheers

Pete

-------------------------------------------

Correct, everything must be taken care of within the single cluster as no separate cluster will be used for anything until LMS failover is triggered.

If they are steadily growing the AP base, go with a couple of 9240 Gold for the primary and move the three 7210 over to the secondary cluster.

hi Carson,

thanks for getting back.

yes you're right my explanation is a bit ropey.

i now think i know what the issue is.

as discussed 3 x 7210's in Data Centre gives a capacity of 1536 x AP's except when the AP's are in a cluster

the quantity is halved.

So the customer is getting NO standby controller on AP's that are over and above this quantity (768 x AP's).

i think they will need extra controllers to facilitate their requirements.

regards

Pete

Clarify please?  I don't think you actually asked a question.

Best guess answer:  The Backup LMS is only ever used if none of the cluster nodes that are part of the LMS cluster are responding.  Your primary site has to be entirely offline for the AP to switch over, not just denying the AP a connection.

------------------------------
Carson Hulcher, ACEX#110

Original Message:
Sent: Dec 15, 2025 04:22 AM
From: peter.elms
Subject: controller clustering with LMS backup LMS

HI Airheads,

i have a customer who has 6 x Aruba 7210 controllers 3 in DATA CENTRE cluster and 3 in DISASTER RECOVERY CENTRE (DRC).

They have 700 x AP'S spread across 3 x 7210 controllers in data centre and if data centre goes down the DRC cluster takes over.

This failover is achieved through use of LMS and Backup LMS in the AP system profile.

The failover works great and with a pre-emption set that works just great.

However...  customer has noticed that when they start to add more AP's (>700) they are not showing the the backup LMS (200 approx.)

I'm going to do some debug but jus thought i would ask the experts what they think of my configuration ?

i was hoping with a capacity of 3 x 512 AP's that i would be ok ?

cheers

Pete

-------------------------------------------

quick question Carson,

when purchasing the 9240 GOLD i can then use the current licence pool of 950 MM-VA licences and AP,PEF and RFP licences (same quantity) ?

Correct, everything must be taken care of within the single cluster as no separate cluster will be used for anything until LMS failover is triggered.

If they are steadily growing the AP base, go with a couple of 9240 Gold for the primary and move the three 7210 over to the secondary cluster.

hi Carson,

thanks for getting back.

yes you're right my explanation is a bit ropey.

i now think i know what the issue is.

as discussed 3 x 7210's in Data Centre gives a capacity of 1536 x AP's except when the AP's are in a cluster

the quantity is halved.

So the customer is getting NO standby controller on AP's that are over and above this quantity (768 x AP's).

i think they will need extra controllers to facilitate their requirements.

regards

Pete

Clarify please?  I don't think you actually asked a question.

Best guess answer:  The Backup LMS is only ever used if none of the cluster nodes that are part of the LMS cluster are responding.  Your primary site has to be entirely offline for the AP to switch over, not just denying the AP a connection.

------------------------------
Carson Hulcher, ACEX#110

Original Message:
Sent: Dec 15, 2025 04:22 AM
From: peter.elms
Subject: controller clustering with LMS backup LMS

HI Airheads,

i have a customer who has 6 x Aruba 7210 controllers 3 in DATA CENTRE cluster and 3 in DISASTER RECOVERY CENTRE (DRC).

They have 700 x AP'S spread across 3 x 7210 controllers in data centre and if data centre goes down the DRC cluster takes over.

This failover is achieved through use of LMS and Backup LMS in the AP system profile.

The failover works great and with a pre-emption set that works just great.

However...  customer has noticed that when they start to add more AP's (>700) they are not showing the the backup LMS (200 approx.)

I'm going to do some debug but jus thought i would ask the experts what they think of my configuration ?

i was hoping with a capacity of 3 x 512 AP's that i would be ok ?

cheers

Pete

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