Did DBD::Oracle install without any problems? In your post you mention the instant client installation after the perl stuff, you had this installed before you built the perl stuff, right? From experience you often get more information when a segmentation fault occurs, please post exactly what is displayed. What do LD_LIBRARY_PATH and ORACLE_HOME contain?

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
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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
my ENV variables in bash_profile:

export LD_LIBRARY_PATH=/usr/lib/oracle/12.2/client64/lib
export ORACLE_HOME=/usr/lib/oracle/12.2/client64/
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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.

Hello ksbehal,

Welcome to the Monastery. I was looking through the web regarding your problem and I found this article (Segmentation Fault (core dumped) while connecting to Oracle using DBD::Oracle):

...After having spent several useless hours trying to find an answer to this question on both Google and Metalink, and then trying to decipher stack trace output from core dump, it turns out that there was no setting in my .profile (in some cases, .bash_profile) file for LD_LIBRARY_PATH.

Can you execute this on your LinuxOS terminal as fellow Monk marto is proposing:

$ echo $LD_LIBRARY_PATH
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It should return the $ORACLE_HOME/lib directory. If it does not return anything you need to set the .profile (in some cases, .bash_profile) file for LD_LIBRARY_PATH.

Let us know if this resolves your problem.

Best Regards, Thanos

I have the LD_LIBRARY_PATH and ORACLE_HOME updated in .bash_profile already

export LD_LIBRARY_PATH=/usr/lib/oracle/12.2/client64/lib
export ORACLE_HOME=/usr/lib/oracle/12.2/client64/

[lroot@slc11zrg ~]# echo $LD_LIBRARY_PATH
/usr/lib/oracle/12.2/client64/lib
[lroot@slc11zrg ~]# echo $ORACLE_HOME
/usr/lib/oracle/12.2/client64/
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