Registration

[Planetmaker]

What could cause a device to drop its registration?
In the past I have had the odd ATA lose it registration - which I have got around by deleting and readding the device on call manager which sometime works and some times doesn't.
Today we have had 5 + phone in the same location come up with "duplicate IP address" which has been cleared once we have rebooted the phone.
One other phone will not register whatever I do. There are planty of spare IP address's for the subnet.
There were no duplicated IP address when I looked on DHCP though....

 

[Dtravler]

Looks like a DHCP problem. Can the phones reach the DHCP server al all times. At 50% of the total lease time it asks the DHCP server if it can maintain it's ip-address.
But I suppose you figured that out already?!

One other possibility is that the phones get an IP-address of a server in your data (v)lan. If that's the case you can set all phones to an permanent TFTPserver. Or change your VLAN design, or change DHCP server options.