Downgrade software on SPA525G2 phone

[kyle.debeus]

We are trying to downgrade the software on two new SPA525G2 phones that were purchased by a customer to match the rest of the phones in their network. The phones came with software version 7.5.5a and the rest of the phones in the network are running 7.5.2(u2). When going through the manual software downgrade through the web interface the phones comes back with a message indicating that the 7.5.2a package is not for this model of phone. When attaching the phones to the voice network they are continuously trying to downgrade the firmware from the UC320W system and rebooting.

Any help would be helpful.

Kyle

[Dan Lukes]

You can't downgrade from post-7.5.2b firmware to pre-7.5.2b firmware.

If like to live on edge, you can destroy saved firmware inside the phone and then use SOS recovery procedure to flash pre-7.5.2b. Note - if the firmware used during recovery will choke on configuration saved in phone, your phone will turn into irreparable brick. Reset your phone to factory default before the procedure, but it may be bricked despite of it. You has been warned.

If you don't wish to live so hard, you should consider upgrade of rest of your network to something less ancient than 7.5.2. Of course, such upgrade may cause other issues ...

[kyle.debeus]

I appreciate your out of the box thinking and we have tried to make the fail the firmware flash at multiple points but not been able to get it to fail.  Is there a particular point that power cycling the phone during the flash will accomplish this or some other method to make it break.  With the flash intact the SOS refuses to put on the older firmware.  If we can get a flash to fail / be corrupted the hope would be that this check may not happen allowing for the older phone firmware supported by the UC320 to be flashed.

I understand the associated risks with this and am prepared for the possible outcome being a bricked phone.

[Dan Lukes]

I didn't missed your response. Unfortunately, I'm in my other office where I have no SPA525G for tests. I tried it on SPA504G. I will return within week or two, I will try to corrupt my SPA525G then.

[Dan Lukes]

Well, I lost. It is easy task on SPA50x but I'm unable to broke internal firmware using power cycle on SPA525G2. It is either because lack of luck (more patience may help) or because there is something like dual-firmware feature implemented in SPA525G2 (old firmware is not deleted nor deactivated unless new firmware is successfully saved and activated). In such case we are out of luck to brick the phone.

Are you running latest firmware on UC320W (2.3.2) ? Consider upgrade if not. Don't forget to read Release Notes in such case.

Note that UC320W has been announced to become End-of-Life. As End of SW Maintenance Releases Date did not occurred yet, you may ask Cisco support for help if latest firmware will not solve your issue. But do not put much hope in it ...

[Dan Lukes]

Note there si something I has not been aware of at the time I responded to you.

If your SPA525G2 phones are the new hardware models that have the 128MB Flash then the lowest firmware they can go to is 7.5.5a.

[stacy logesky]

did you ever get this issue resolved? if so, how?

I'm in the exact same situation

Thank you

[kyle.debeus]

We never ended up getting this resolved....our client decided to have the phones returned since they weren't working with their system.