ASR920-12SZ-IM in FPGA downgrade loop

[PK99]

We have a ASR920-12SZ-IM that was running IOSXE 15.6.2 perfectly fine.  Upgraded unit to 16.5 and it upgraded the FPGA automatically.  Then it rebooted, then we noticed that after it reboots, it keeps stating that FPGA needs to be upgraded and goes in an upgrade loop.  We then tried 16.7 and same thing happened.  Then we took unit back to 15.6.2 and it now says

*Mar 17 03:41:56.755: %HANDOFF_FUD-6-HOFPGA_DOWNGRADE: R0/0: cylon_mgr: Handoff FPGA is downgrading to 0x10010 from current FPGA version 0x3001b, as downgrade is required for current release
*Mar 17 03:41:56.756: %HANDOFF_FUD-6-HOFPGA_DOWNGRADE_STARTED: R0/0: cylon_mgr: Starting Handoff FPGA downgrade

Now it keeps looping to this.  We then tried back 16.7 and the above message keeps appearing.  Router is in a reboot loop.

Anyone experience this or have any solutions?

Thank you!

[PK99]

To add to this, I just learned router was running 16.12.  Could it be that we have to downgrade to 16.11 first, then downgrade to 16.7?  I'm guessing that 16.12 upgraded the FPGA to 0x3001b and maybe 16.11 will take it down to 0x10010 where 16.7 can't really take it down to it?

[marce1000]

 - Following this document  : https://www.cisco.com/c/dam/en/us/td/docs/routers/asr920/syslogs/ASR920-SysMsgs.pdf , the messages should be informational (only), which is clearly no what you are experiencing. Any (other)  last messages before the reboot(loop) and or post a trail of what is happening.

 M.

[PK99]

Thanks, we reloaded 16.12.5 and the message is gone.  So my guess is, in order to go to 16.7.1 we MUST downgrade to 16.12.1-4 or 16.11.X before going to 16.7.X but we can't find any documentation as to which version we have to go to first in order to go to our target version.