SPA525G2 firmware downgrade

[cisconaut]

Hello all, PLEASE HELP! I urgently need to downgrade the firmware in a SPA525G2 from 7.6.2c to 7.5.2...which, according to docs, should be working whne setting the parameter "downgrade rev limit" in the web GUI to a lower value (e.g. 7.4.8). Still, the phone denies being downgraded with a "Forbidden image for this hardware" message. The image in question is perfectly OK, as it was accepted and working when upgrading. Now I have to revert to a lower rev. I have several 7961 phones brought back to life by completely erasing with the "magic" key sequence and then tftp'ing new FW onto it. I guess such should be feasible with the SPA525 also, but I cannot find appropriate documentation, no matter how hard I google. So, if someone of "the old days" team is out there, please help! Regards, André

[mridsing]

Hi  cisconaut,

Thanks for your Post, Kindly request you to check cross verify the serial number of SPA 525 G2 to verify the hardware and firmware compatibility for downgrade to 7.5.2.

(Hardware and Firmware Compatibility
The following matrix describes the hardware and firmware compatibility.)

Firmware version :- 7.6.2 (release notes) by downloading the ZIP file.

https://software.cisco.com/download/release.html%3Fmdfid%3D282414147%26softwareid%3D282463651%26release%3D7.5.6

PFA..(release notes of firmware release 7.6.2)

Regards,

Mridul

[cisconaut]

Hello, will do as soon as I'm home, but that ain't the problem, I guess...the particular phone had 7.5.4 on it before, I upgraded to 7.5.6 and then to 7.6.2c, but the way back aka downgrading is not possible, I have no idea why the newer FW rejects being downgraded - possibly that's an option that nobody tried before? In fact, in the Web GUI und "provisioning" there is this parameter field "Downgrade rev limit", empty by default; when filled with e.g. "7.4.8" the phone is meant to accept any FW version above or equal. Quite obviously, I am the first one to actually try a downgrading. According to the documentation, the format for that field is x.y.z, it accepts longer strings also, maybe there's a fault there? Regards, André

[cisconaut]

Cont'd... Anyway, the best solution is to modify the UC320W firmware such that it accepts higher SPA525 phone FW than 7.5.2. That is my core problem, as soon as I connect the phone to the UC320, it "sees" a FW not-equal 7.5.2 and starts an update process, that again being denied by the phone as downgrade attempt...classical deadlock, do you agree? If any of the SMB/UC320W team is left over, I am convinced, could cure that with a so-called PMF-file (a means of minor software bug fixes) if they still know how to generate it. Or by means of telnetting into a CLI ... Ceterum censeo, I should have the telnet credentials and service/programmers documentation... Merry Christmas anyway André

[mridsing · Accepted solution]

Hi,

Thanks for your reply , with the  modify the UC320W firmware can be a possible solution.

I am able to pull out similar case where the downgrade of SPA525 G2 7.5.4 was tried but unsuccessfully.

Reason:- 

 - Attempted to change firmware
 - Error: "Forbidden image for this hardware
 - Reviewed SN and determined SPA525G2 is newed HW, downgrade is not possible

DOWNGRADE on newer SPA525G2 is not possible, since Cisco has upgraded 128MB memory, incompatible with older FW versions. FW 7.5.5a is the lowest it can go

 PFA.. SPA525 G2 128 flash.

Merry Christmas.

Regards,

Mridul 

SBSC

[cisconaut]

So I'll test with 7.5.6, which should go well according to your info. I'll be able to test that within next 2 hours, I'll let you know.

But when I'm not terribly mistaken I started off with 7.5.4 on this phone...

Thank you very much so far,

André

[cisconaut]

Seems I was mistaken...I did not start from 7.5.4, must have been 7.5.6. Yes, downgrade to 7.5.6 (from 7.6.2) is possible. OK, now I have an explanation but not really a solution, and the range of possible solutions has narrowed down considerably. Let's hope for the expertise and goodwill of the UC320W team.

Merry Christmas and thank you

André