Previous log and diff

Shell Programming and Scripting
1

Logs are created on a daily basis, the format of the log file is: servername_yymmdd. I need to check if there is a difference in the log created today with the previous one. I would appreciate help on how I can step back to the previous log and how can I test if there is a diff in the logs.

Thanks you.

2 
man diff
3

There are dozens of examples finding yesterday's date on the forum. Try a search, or go to the FAQ and look up the thread on date arithmetic - datecalc script

4

here is one example of finding yesterday's date :

date -d "yesterday" +"%d %b %Y"
5

Thanks everyone, really appreciate your help