DHCP Option 43 - Secondary Call Server

[SaladChest]

Hello,

Our current Option 43 configuration is:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115

Where 10.2.0.115 is our primary MiVoiceBusiness server. Our secondary server is at 10.2.4.3 and needs to be added so that phones can fail over to it in the event that the primary goes down.

Our phone vendor thinks (but isn't certain) that we can simply add this secondary server to the end of the string with comma separation as such:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115,10.2.4.3

Can anyone confirm if this will result in proper failover for the phones?

Thanks

[acejavelin]

Yes and no... This isn't related to the resiliency, that is gotten from the controller AFTER successful bootup... This will tell the phones to try the primary call server first, then the secondary, and up to 4 RTC controllers total, in order when initially booting up.

This will NOT cause or implement resiliency... the phones secondary controller is given to it at the time it registers to the controller.

[lundah]

Hello,

Our current Option 43 configuration is:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115

Where 10.2.0.115 is our primary MiVoiceBusiness server. Our secondary server is at 10.2.4.3 and needs to be added so that phones can fail over to it in the event that the primary goes down.

Our phone vendor thinks (but isn't certain) that we can simply add this secondary server to the end of the string with comma separation as such:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115,10.2.4.3

Can anyone confirm if this will result in proper failover for the phones?

Thanks

Yes, this is how you assign the secondary ICP in the DHCP options. The phone still has to have it programmed as well, or as soon as it comes up to the primary the secondary ICP value will be removed from the phone. But using the comma+ second ICP address will allow the phone to boot to the secondary if the primary is unreachable from the phone.

[ralph]

Back "in the old days" we did it that way.
The problem was, if the phone wasn't programmed to be resilient then if the primary controller went OS, the phone would try to register to the secondary server and would sit there asking for a pin. When the primary controller recovered the phone couldn't. It had to be rebooted manually.

Ralph

[SaladChest]

Hello,

Our current Option 43 configuration is:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115

Where 10.2.0.115 is our primary MiVoiceBusiness server. Our secondary server is at 10.2.4.3 and needs to be added so that phones can fail over to it in the event that the primary goes down.

Our phone vendor thinks (but isn't certain) that we can simply add this secondary server to the end of the string with comma separation as such:

option 43 ascii id:ipphone.mitel.com;sw_tftp=10.2.0.115;call_srv=10.2.0.115,10.2.4.3

Can anyone confirm if this will result in proper failover for the phones?

Thanks

Yes, this is how you assign the secondary ICP in the DHCP options. The phone still has to have it programmed as well, or as soon as it comes up to the primary the secondary ICP value will be removed from the phone. But using the comma+ second ICP address will allow the phone to boot to the secondary if the primary is unreachable from the phone.

Thanks, so is this something that can be configured in the phone server then to ensure the phones are always aware of their failover server? Or do you mean each phone would have to be programmed individually when a failure occurs on the primary phone system server?

Thanks

[ralph]

In the User and Device form you select what controller is the device's resilient controller.  When the phone boots, it get's its resilient controller information from the server. No need to put it in the DHCP scope at that point.

Ralph

[SaladChest]

In the User and Device form you select what controller is the device's resilient controller.  When the phone boots, it get's its resilient controller information from the server. No need to put it in the DHCP scope at that point.

Ralph

That makes sense, thanks. But I'm wondering if I'm looking in the correct place. Is this defined at the location below?

Users and Devices > User and Services Configuration > [Select a Device] > Service Profile > Secondary Element

It sounds like the phone gets this configuration upon boot, so I'd need to reboot each phone for it to get this configuration?

And then each phone will retain the IP of its secondary element indefinitely? (e.g., if I define the secondary element today, reboot the phone tomorrow while the primary element is up and working, and then on day 3 if the primary element goes down, the phone will failover to its secondary element as normal?)

Thanks again for all your help.