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Cisco Bug: CSCvs18851 - Router goes into a continuous boot-loop when downgraded from newer to older versions.

Last Modified

Jul 16, 2020

Products (1)

  • Cisco ASR 920 Series Aggregation Services Router

Known Affected Releases

16.12.2 16.9.4 17.1.1

Description (partial)

When downgrading routers from 17.1.1, 16.12.2, 16.9.4 etc to older releases such as 3.18 SP, 3.16 SP etc.
Router is going into a continuous boot-loop.

Following logs will be displayed during bootup :
FPGA UPGRADE Done: System going for reboot 
System Bootstrap, Version 15.6(10r)S, RELEASE SOFTWARE (fc1) Technical Support: Copyright (c) 2016 by cisco Systems, Inc. Compiled Thu 24-Mar-16 15:38 by alnguyen Boot ROM1 Last reset cause: PowerOn UEA platform with 3670016 Kbytes of main memory
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