Hi, arvindblabs, welcome to the monastery. It's not a soup kitchen.

If you find yourself doing eight steps to generate a filename, you are probably not using Perl's built-in functions. Try to find them ... you can make a good guess that yes, Perl has a function for x and then search.
If you do perldoc -f date on your terminal you will see what I mean.

Also, don't use backticks to run system executables, you won't get any errors back.

#!/usr/bin/env perl -w
use 5.010;
use strict;

use POSIX qw/ strftime /;
my $date = strftime "%Y%m%d", localtime;

say join '.', (join '', $_, $date), 'tar.gz' for qw/ bugs_db_ bugzilla
+_ /; 
__END__
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