my code snippet which makes connection and the variables used in connection string is already having valid values defined

%attr = (
    PrintError => 1,
    RaiseError => 1,
);


$driver= "Oracle";
$dsn = "DBI:$driver:sid=$db_name;host=$host";
eval {
        $dbh = DBI->connect($dsn, "$user", "$passwd", \%attr);
};if($@){
        print "ERROR with connection: $@\n";
}

print "Hello";

o/p: 
[lroot@slc11zrg ~]# perl_5.22  db.pl
HelloSegmentation fault
[download]

Existing conf: Oracle Linux 7.x, Perl5.16 already installed Process I followed:-

1. installed CPAN manually
2. installed DBI make install says ok
3. Installed Oracle instant client in the same linux box
4. DBD::Oracle make install completed ok, but can see logs like "cant establish oracle connection"
5. Installed other required modules

export LD_LIBRARY_PATH=/usr/lib/oracle/12.2/client64/lib
export ORACLE_HOME=/usr/lib/oracle/12.2/client64/
[download]

both paths are good and contain the Oracle instant client

Please let me know If I can give any further inputs.

Thanks,
Kuldip

2018-12-01 Athanasius added list and extra paragraph tags

"perl_5.22 db.p" ... "Perl5.16", do you have multiple versions of perl installed?

'but can see logs like "cant establish oracle connection"'

You'll see these unless you set some environment variables before installing. See Re^3: DBI AND ORACLE 8 and the module documentation.

Yes, first I had only Perl5.16 and it was having the same "Segmentation fault" later I tried it with Perl5.22 but error is same again.