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*Resolved* BLF Failback to Primary Server - DNS-SRV - Printable Version

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*Resolved* BLF Failback to Primary Server - DNS-SRV - Bryan Nelson - 04-16-2013 07:03 AM

---Original Message bounced back form


We are having an issue with BLF status subscriptions when combined with the DNS-SRV functionality. The BLF keys will work fine until the phone utilizes the secondary server listed in the DNS-SRV record. After registering to the secondary server, all 200 ok responses to notify events are sent to the secondary server, even if the phone has reverted back to its primary registration.

Without the 200 ok responses, our server will queue up further notify events to avoid a "notify storm" on the phones end(the server assumes the phone is lagging behind the notify events.)

Is there any way to lock the BLF subscription to a specific server address, rather than use the line registration SRV record? Polycom phones had a similar issue, and we were able to specify an a-record lookup for the BLF subscription separately from the line registration server address.

I have attached the pcap\config\logs from the phone -- A T-26. Let me know if you need anything else from me to help identify this problem.

RE: BLF Failback to Primary Server - DNS-SRV - Bryan Nelson - 04-17-2013 03:03 AM

Would setting the out-of-dialog BLF to enabled help in this situation? Upgrading to 70.140 did not seem to help, but I dont' know if it addressed in the upgrade. Are there specific release notes for each firmware revision?

RE: BLF Failback to Primary Server - DNS-SRV - Bryan Nelson - 02-07-2015 06:03 AM

This is an old thread, but we did find a solution thanks to Yealink's support team!

Setting the phone to use the outbound proxy, set to the same SRV address will resolve the issue. Basically, this will force BLF requests to be "proxied" to the SRV address, rather than just continuing the current subscription after failover to the backup server.

RE: *Resolved* BLF Failback to Primary Server - DNS-SRV - Agrajag - 10-18-2015 02:35 PM

I'm having a similar issue with my 46G. I'm trying to get it to work with ThinkingPhones (they basically only support Polycom phones) and I had it working flawlessly. Then, suddenly, the account would register but it would no longer receive calls. Soft phone tests work just fine, but NOT this phone. It's to a point where I'm thinking of returning the phone for another brand.

I do the exact above work-around. However, at some point the phone dumped to their backup server which does not allow for outbound calling. Now, no matter what we try, the phone will not get off the backup server. It's forever stuck using it.

RE: *Resolved* BLF Failback to Primary Server - DNS-SRV - davebenwell - 11-11-2015 09:12 PM

Did you resolve this?