spectalink phones load balancing issue

[vijendra Saravanamuthu]

hi guys, wondering if anyone ran into this issue and if there is a possible workaround for this.

we got cucm 11.5 and trying to get spectalink 8440 registered. the registration is working it just that we cannot load balance them between 2 subscribers. (For ex, if we have 20 spectra phones, I want 10 to on one sub and another 10 on other sub).   by default "

Spectralink 84-Series Handsets support failover between two or more SIP servers natively.
However, if your SIP environment uses active-active failover, meaning that your SIP servers are
aware of each other and keep track of client states, then you will want to use DNS to configure
your failover. The default failover behavior for the 84-Series handset assumes that the SIP
servers are setup as active-passive, meaning that when one SIP server is active the other is in
a standby state and unaware of the client registration of the other server"

https://support.spectralink.com/sites/default/files/resource_files/CS-14-17%2084-Series%20Failover%20Configuration%20Using%20DNS_0.pdf

cucm subscribers are active-active fashion so only way to do is thru DNS srv .  so we created dns SRV as mentioned in this article.

https://support.spectralink.com/sites/default/files/resource_files/CS-14-12%20Domain%20Requirements%20in%20Spectralink%20SIP%20Phones.pdf

if we create srv with same priority and weight and point to both subscribers, spectra link flaps between both subscribers when registering.  if we change the priority to higher for one of the SRV , specta regsiters to that sub and works fine.  but of course, now all spectra register to that one sub. no load balancing. 

anyone has any idea, pls let me know if there is any other option we can try for load balancing.

thanks

vijay

[Prashant Sharma]

Hi Vijay,

Let me know if you have added SRV for both registrar server and you have used CCM group for load balancing. If not from CCM side you can use two CCM group, one with primary ccm node up in the order and same for other group with other sub in the higher priority for load balancing. In that case phone will only request for its primary node for registration and will keep connection with Secondary for fail over.
You can refer the below mentioned reference doc for SpectraLink Phones :

https://support.spectralink.com/sites/default/files/resource_files/1725-86980-000_C2.pdf

Regards,
Prassha3

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[vijendra Saravanamuthu]

Hi Prashant,

thanks for you response.  yes I do have Device pool with different ccm groups.  but spectra phones only register with the ccm which received from querying the SRV.  the device pool or its associated ccm group are not downloaded to the spetra phone as it does by cisco phones.

as I mentioned above, SRVs are configured with 2 ccm and one of them has a higher priority. so spectra will always registers to that ccm.   the only way I can think of now is to create another subdomain and SRVs and this time I set the priority on the other sub.  but for each scenario, I manually have to put in the subdomain into the sptra phone configs.