What is the "Backup IP" reboot reason on the Cisco SPA 50x IP phones

[mullness]

Submitting a question on behalf of a partner:

Hi,

We  have a customer, at a remote site with SPA504G phones, they have a  problem with the phones rebooting once in a while, typically once an  hour.

In the reboot history on the phones the reason is "Backup IP".

I cant find any reference to this in the SPA 50x manuals or anywhere else, so what do this actually mean?

The phones are deployed using SIP, and are running firmware 7.4.9c.

The phones /admin/status.xml has this information:

<    <Reboot_Reason_1>Backup IP(01/01/2003 12:00:00)</Reboot_Reason_1>

      <Reboot_Reason_2>Backup IP(04/25/2012 07:43:29)</Reboot_Reason_2>

      <Reboot_Reason_3>Backup IP(04/25/2012 06:40:45)</Reboot_Reason_3>

<    <Reboot_Reason_4>Backup IP(04/25/2012 05:38:02)</Reboot_Reason_4>

      <Reboot_Reason_5>Backup IP(04/25/2012 04:35:18)</Reboot_Reason_5>

The manual has information about several other reboot reasons, but I can't find any information about this "Backup IP" reason.

- Martin Mikkelsen, Zisson AS

[nseto]

It's unable to renew the ip address via dhcp, so it's using the previously stored ip address.

If there's an issue with the dhcp, you can set static ip address on the unit so there's no more reboot due to dhcp issues.

[mullness]

Thanks for the help, much appreciated!