Om Prakash Jaiswal wrote:
> I installed RHEL7.3 64 bit is enterprise version.Downloaded postgresql9.6.3 64 bit for Linux.Installed in /opt directory.
> RPM -ivh postgresql9.6-plperl96.rpm.Find libperl.so. it was at /usr/lib64/perl5/CORE directory.vi /etc/ld.so.conf.d/libperl.conf < /usr/lib64/perl5/CORE ldconfig
> vi /etc/ld.so.conf.d/libpostgres.conf</opt/postgres/9.6/lib
> reboot machine.Now create extension plperlu.Error /opt/postgres/9.6/lib/postgresql/plperl.so undefined symbol: Perl_save_strlen.

Most likely this indicates that the plperl.so is compiled against a
different version of Perl than the one that provides libperl.so.

I don't understand what you installed (or rather, you did not say), but
I suspect you have a weird (unsupported) combination of packages.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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