Downgrade one IP phone

[Jaro]

Hello, I need to downgrade one Cisco phone 7811 with version 11.0.1.11 due to bug with no missed calls to version 10-3-1-12. I need to downgrade only one device for test, this device it is not in CME.

I´m quite new in voice, so could you help me. 

Thank you 

[Jaime Valencia]

I'll assume CUCM, go to the device you want to downgrade, and input the FW file you want in the load name option, save and apply the config.

[Jaro]

Hello, I´m using fast track and it is configured on a SW as CME 10.5 (Cisco Unified Communications Manager Express ), phones 7811 are using SIP protocol, and it is not visible in CME (I have phones 6945 which are visible in CME working with SCCP protocol) it looks this is another problem or it should behaviour by that way ?

Phones 7811 are not configured as ephone, because my switch not support  7811 so they are configured by fast track.

Questions summary:

1. What I should add or change in my configuration , if my phones are not visible in CME GUI (I can see registered phones in cli, if I enter : show voice registered.) ? 

2. How can I downgrade one device 7811, without CME (if it will not work) or with CME if I will solve it ?

3. Could you please send me some document or some links with detailed approach ?

Thanks in advance

[R0g22]

1. First thing, upgrade your CME to 11.0 or higher. CME 11.X added native support for these phones. No need to have fast-track now.

2. SIP Phones are not supported on CME GUI, even with the latest 12.X version. That's a limitation.

3. Why are you looking to downgrade the phone firmware ? You might not be able to downgrade the firmware if these are a new batch and have a higher hardware revision.

[Jaro]

Hello, thank you for your answer.

I need to downgrade cisco phone 7811 because of a bug with missed calls (no log with missed calls on display of the phone), so if you don´t pick up the phone, you will not know that someone called you, so I found out that downgrade should help or do you have any idea, how to solve it instead of donwgrade?

Are there any configuration changes, when you compare CME 10.5 and 11, I´m asking, because of in our company there are more than 200 phones. ?

Thank you 

[R0g22]

I have seen that defect. You can upgrade to 15.6.3.M3 IOS or above. From a configuration point, you don't need to do anything for the IOS upgrade. A couple of things do keep in mind though -

1. You would need to add CME GUI files for the upgraded CME version. With the older files, your CME GUI will stop working.
2. Any other phones that you have apart from 78XX, you would need to check what the compatible firmware is on the upgraded CME version. If you do not meet the req, you would need to upgrade the firmwares on all of those phones.
3. If you are using CUE, ensure that your CUE version will still be compatible with the upgraded CME version.

[veimar]

Amigo, encontraste la solución? tengo el mismo problema

[Roger Kallberg]

Advice you to write in English in this community post as that’s the language others have used.