Cisco 6921 IP Phones lose its IP address

[GHARIP MOHAMED MARZOK]

i faceed this issue with many 6921 phones , it take static IP and suddenly it lose its IP and stop working and after readding the IP it work again,

any one can advise ?

[paolo bevilacqua]

Try update phone firmware. For best results use DHCP not static address-

[Gordon Ross]

One thing to watch out for with Cisco IP Phones, is that dynamic configuration from the network can override any static configuration. Not sure if this applies to IP Addresses, but I've seen other static parameters get overridden by network settings.

GTG