Phone registration

[Lasha Lomjaria]

Hello,

We have problem with registering cisco 6921 phone to CUCM 8.6.

We have about 400 phones and most of them are working fine, but some of them not registering.

They get ip address from DHCP, I can see phones as CDP neighbors but I cannot reach them. Ping doesn't work.

I tried to plug another phone in same switch port and it worked. Do you have any ideas?

[Tagir Temirgaliyev]

hardware fault

or firmware bug

I had  firmware bug 9.1.1.0

[Lasha Lomjaria]

Other working phones have same firmware, so it looks like hardware fault...

thank you.

[Tagir Temirgaliyev]

check firmware. probably you need latest.

[Tagir Temirgaliyev]

actually it is not the problem between cisco 6921 phone and CUCM 8.6.

if you can not ping 6921 phone from L3 switch so it is problem in IP or DHCP level or in VLANs or in subnets

[Lasha Lomjaria]

thanks for reply,

When I connect another phone to same switch port it works fine, so its not Vlan and dhcp problem...

[islam.kamal]

Hello

1- Kindly do a factory reset for your phones which have problem.

if problem still exist

1- make sure that your IP phones one the correct voice vlan , check your L3 , check your intervlan configuration

if the problem still exist

1-go to phone physcially - setting - security setting - erase CTL & ITL .

if the problem still exist

1-try to connect one of the Ip phones which is registered properly before to the switch port which connected to ip phone which unable to register .

Thanks

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