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?

[Richard Simmons]

Hi,

Have you tried a Factory Reset on the effected phones?

Step 1 Unplug the power cable from the phone and then plug it back in.
The phone begins its power-up cycle.

Step 2 While the phone is powering up, and before the Speaker button flashes on and off,
press and hold #.
Continue to hold # until each line button flashes on and off in sequence in amber.

Step 3 Release # and press 123456789*0#.

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/6921_6941_6961/7_1_2/english/admin/guide/69214161AG/6921trb.html#wp1031705

Regards,

Richard

[Lasha Lomjaria]

This factory reset doen't work on 6921 phones...

I tried reset all setting from applications menu, but still the same problem...

[islam.kamal]

Hi

1- For reset factory , check the below:-

https://supportforums.cisco.com/discussion/11436876/69216941-factory-reset

2-Did you erase the CTL & ITL from device physically - setting-**# - security setting - ctl & itl erase.

3- Can you chech the firmware of 6921 which unable o register ?.

Thanks

please rate all useful information

[Lasha Lomjaria]

Hi,

1. Factory reset doesn't work on 6921, I had tried it before...

2. I erased CTL & ITL.

3. firmware is SCCP69xx.9-3-1-3

[Richard Simmons]

Are there enough IP address available in the DHCP scope, can you verify the phone is getting an IP from the correct DHCP server and validate the settings show the same on the phone menu?

As a known working phone can be connected to the same switchport and work we can rule out issues with the switchport configuration but the phone will be maintaining its DHCP lease.

[Lasha Lomjaria]

Hi

I've already checked DHCP.

1. IP addresses are available in DHCP scope.

2. Phone gets IP address from valid dhcp server, and when I checked on server and on phone, both addresses are same.

[Richard Simmons]

Just to confirm you can ping a working phone but you can't ping a none working phone?

[Lasha Lomjaria]

Yes, that's right. I can ping working phone but can't ping none working phone.

[Richard Simmons]

When you connect the working phone are you using the same ethernet cable or do you also change that? If you haven't already try a different - known working - ethernet cable

[Lasha Lomjaria]

I use same cable, seems like hardware fault... 

[Richard Simmons]

It could be a hardware fault, might be a dodgy batch.

You could also try configuring the IP Address, Subnet Mask, Default Gateway and TFTP Server manually on the phone to see if you can then ping it and if it will then register to CUCM 

[Lasha Lomjaria]

I've already tried it but no success. still same problem

[Richard Simmons]

Do you definitely have the right default router/gateway set - I have seen it before that when this is incorrect you are unable to connect to the phone.

[Lasha Lomjaria]

Richard

default gateway is correct - as other network configuration...