IP phone 78xx firmware downgrade from sip78xx.10-3-1-12 to sip78xx.10-2-1-12 as workaround for Expressway

[Isai Reyes]

Hello people

Recently we updated firmware for phones 78xx (7821 , 7841 , 7861) in CUCM (System version: 8.5.1.10000-26) from firmware version "sip78xx.10-1-1-9" to "sip78xx.10-3-1-12" this as a workaround of problem phones won´t register in CUCM.

Now some phones show a "sign in" screen when phone comes up (Image 1).

As per documentation (1) found in firmware releases this is due Expressway feature is included as a beta version for firmware release 10.3(1)

This feature is not currently implemented in our enviroment this is reason why we cannot use these phones when the sing in screen appears.


Expressway feature is not included in firmware release 10.2(1) so i tried to downgrade firmware but after i upload file "cmterm-78xx.10-2-1-12.cop.sgn" to the CUCM, restart TFTP servers (both publisher and subscriber), and restart phone the firmware stills the same "sip78xx.10-3-1-12".


In CUCM phone status shows "upgrading" (Image 2) but after a couple min Inactive Load Failure Reason status shows: File Not Found (Image 3).

I verify that Load information in Device Defaults is correct (Image 4) and Load Information field shows "sip78xx.10-2-1-12" also in CLI with "show version active" command (Image 5) even in Cisco Unified OS Administration>Software Upgrades>TFTP File Management I verify files exist (Image 6) so i don´t understand why cannot downgrade to firmware version 10.2(1).

In RTMT SysLog Viewer I find that phone begin to download firmware and later it fails (Image 7)

So ...

Somebody knows how to disable Expressway feature in CUCM for firmware release 10.3(1) or...
Downgrade from firmware release 10.3(1) to firmware release 10.2(1) in 78xx phones?

I'll appreciate any help.
Thanks


(1)

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/7800-series/10-3-1/english/releasenotes/PA2D_BK_70AD4CFB_00_7811_7821_7841_7861-rn-1031/PA2D_BK_70AD4CFB_00_7811_7821_7841_7861-rn-1031_chapter_00.html

[Manish Gogna]

Hi Giezi,

The issue of not being able to downgrade the firmware on certain phone models is related to the hardware revision no associated with them. The 7821 phones with hardware revision 33 do not allow the firmware to be downgraded. If the phones are of a lower hardware revision no then they should allow the downgrade to 10.2 firmware. If its not working then you can collect the TFTP traces and phone console logs from one of the affected phones.

Manish

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[Isai Reyes]

Manish

Thank you for your reply

indeed, not all phones 78xx are able to downgrade firmware from version 10.3 to lower versions:

 The Cisco IP Phone 7821, 7841 and 7861 has hardware updates. The new phone version IDs are:

    Cisco IP Phone 7821: V03

    Cisco IP Phone 7841: V04

    Cisco IP Phone 7861: V03

Phones manufactured with the new version ID must run Firmware Release 10.3(1) or later. The phone firmware does not allow the phone to be downgraded to releases earlier than Firmware Release 10.3(1).

Thanks

1

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/7800-series/10-3-1/english/releasenotes/PA2D_BK_70AD4CFB_00_7811_7821_7841_7861-rn-1031/PA2D_BK_70AD4CFB_00_7811_7821_7841_7861-rn-1031_chapter_00.html#PA2D_CN_NC2454A0_00

[Manish Gogna]

Hi Giezi,

Thanks for updating the post.

Manish

[Gordon Ross]

The sign-in screen only appers if the phone can't talk to CallManager.

GTG

[Isai Reyes]

Thank you Ross

That was actually the problem.

We found that the ports of switches where phones were connected to, had a switchport access vlan that was not the proper one, that vlan didn´t have option 66 configured so they couldn´t reach CUCM.

To avoid problems with inherited configuration we just enabled option 66 in vlan where phones were connected to. After that they could reach CUCM and download firmware.