CUCM 6.x, IP Phone status values

Unanswered Question
Aug 20th, 2009


Please, advice the difference between 2 (two) phone status in CUCM 6.x:

1. Unregistered (with IP-address value assiosiated in adjacent field on the right)

2. Unknown (with Unknown value in the same adjacent field).

See the screenshot I've attached. Thank you.

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Overall Rating: 4.3 (7 ratings)
Jaime Valencia Thu, 08/20/2009 - 06:15

Unregistered = At some point it was registered

unknown = it has never been registered



if this helps, please rate

Adrian Saavedra Thu, 08/20/2009 - 08:02


Also, a phone passes from Unregistered to Unknown when the phone has lost conectivity to CUCM for a while, but I'm not sure how much time must pass for this.

Perhaps Java can correct me if I am wrong in something.

Best regards,

- Adrián.

Jaime Valencia Thu, 08/20/2009 - 09:08

mmm i gotta be honest, at least i've never heard that it would go from unregistered to unknown after X time. You might be right but it would take some time to go into the lab and see if it happens overnight.

If someone else has witnessed that behavior feel free to comment.



if this helps, please rate

Rob Huffman Thu, 08/20/2009 - 09:32

Hi Adrian/Java/Tobivan,

Hope you are all doing well! I have seen phones transition from Unregistered to Not Found/Unknown many times. It does take a fair amount of time after being disconnected for this to happen. How long is "fair", I'm not really sure either ;-)

It's cetainly not overnight, but it may be the length of the DHCP lease. I just checked on a phone I disconnected about 3 weeks ago and it now shows the Unknown state. I believe if CUCM is re-booted when the phone is disconnected it changes state as well.

Maybe we should all do a test and report back. I just unplugged one of my Lab phones, so I'll keep an eye on it and see when it changes.



Rob Huffman Fri, 08/28/2009 - 04:54

Hey Guys,

Just to update, the 7942 that I unplugged on August 20th has now transitioned to "Not Found". Our DHCP lease is one week so I'm guessing that if the IP Phone is unplugged when the renewal comes up it moves to Not Found/Unknown.



Tobivan_Helden_2 Sun, 08/30/2009 - 22:08


The phone goes through Unregistered>Unknown state indeed.

I can only confirm currently the timeout is more than 24 hour.

Sourabh Mudgil Sat, 09/29/2012 - 11:12

Hi All,

A phone that has never been registered to call manager would definitely be in Unknown status. But, a phone that was registered to the call manager at some point of time can be in Unregistered or Unknown status depending on a service parameter in the "RIS Data collector" service.

The parameter is "RIS Unused Cisco CallManager Device Store Period" :

This parameter specifies the RIS database information storage period for any unregistered or rejected device information from the Cisco CallManager service. After the time specified in this parameter expires, Cisco CallManager removes the expired entries during the next RIS database cleanup time (specified in the RIS Cleanup Time of the Day parameter)

      This is a required field.

      Default:  3

      Minimum:  1

      Maximum:  30

      Unit: day


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