Please note the following documentation when upgrading to Junos OS Release 21.2R1 or newer.
Because Junos OS Release 21.2R1 runs on FreeBSD 12, which uses system calls not available on FreeBSD 10 or 11, you must include one of the following options instead of the  validate  option on the  request system software add  command when installing the package:

• no-validate

• validate-on-host

• validate-on-routing-engine

Please use either  "no-validation|validate-on-host|validate-on-routing-engine" option with the "request system software add" command when upgrading Junos OS based on FreeBSD 10 or lower (Junos 21.1 or earlier) to Junos OS version with FreeBSD 12 (Junos 21.2 or later). See PR1568757 and the "Junos OS Software Installation and Upgrade Guide" for more information.

First publication 2021-12-27

• Junos OS Software Installation and Upgrade Guide
• The image validation is not supported during upgrading from Pre 21.2 to 21.2 and onward