Call Back Features Limitation

[chor-wai.tan1]

Hi All,

I would like to ask about Cisco Call Back features. 

Recently I got a question from my client regarding is there any limit the Call Manager can support the usage of Call Back concurrently.

Currently they have about 22++ IP phones, and what if all the phones use the Call Back features concurrently will Call Manager support it. 

Does it depends on the VM resources?

Seeking advice from the community before I open TAC case for this issue. 

Call Manager Information : 

System version: 11.0.1.22900-14

VMware Installation: 2 vCPU Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz, disk 1: 110Gbytes, 8192Mbytes RAM, Partitions aligned

Thank you everyone. 

[Rajan]

I dont think you need any additional resources just for callback feature.

You can activate and use it on all the 22++ IP phones concurrently.

HTH

Rajan

[Jaime Valencia]

And do they have any data that they actually rely that heavily on call back???

I really doubt ALL of their users would be using call back at the same time.

[chor-wai.tan1]

Hi All,

I got reply from Cisco. Activation call back to how many devices depends on the OVA you chooses.

Let say If 2000 users in a 2500 user OVA with 6GB RAM and 1 vCPU use the Callback function at the same time then there is a very high probability of CPU/RAM spikes and consequently core dumps being generated. However, a 7500 or a 10000 user OVA will provide additional RAM, vCPU and vDisk capability to handle these concurrent requests.

Hope this able to help the community. =)