Hi Arnab,
Yes, you can load the models only from the 10.2.0 into the 10.2.1 database. One thing to note though, is that your catalog will be out of sync if you are in a Distributed SS environment. (If you are not in a DSS, just do steps 4, 5a, 5c, 6, and 7).
So here's what you can do:
1. Take a backup on the MLS and copy that save file to this crashed SS. Put it in the SS-DB-Backup directory (and rename it to have MLS in the name if you want so you aren't confused as to what that was in the future).
2. Unzip the MLS SSdb on the crashed SS. Put it in the SS-DB-Backup directory
3. Unzip your 10.2.0 SSdb save file
4. Remove the $SPECROOT/SS/.VNMDB.LOCK file
5 From the SS directory, run the following from a bash -login:
a. ../SS-Tools/SSdbload -il legacy
b. ./SS-Tools/SSdbload -c ../SS-DB-Backup/MLSsavefilefromstep1
c. ./SS-Tools/SSdbload -m ../SS-DB-Backup/thesavefilefrom10.2.0fromstep3
Once complete, you can manually save it if you want:
6. ./SS-Tools/SSdbsave -cm ../SS-DB-Backup/2017-11-09_backup.SSdb
7. Start the SS
Cheers
Jay