Here's a new thing I found out playing around with ASR IOS_XR, this is a continual followup to another followup on ASR9K chassis serial#;
The show diag chassis cmd from the admin mode will also display the chassis serial number. You must execute this from the admin context.
So now you have a few different ways for acquiring the chassis serial#.
admin show diag chassis
admin show inv chassis
By execution of a QNX korn shell and cat the contents of the license_bkup1 file
NSE ( network security expert) and Route/Switching Engineer
kfelix -----a----t---- socpuppets ---dot---com
=( $ $ )=