I had to move a perl script from an old server to a new one. Both the old and new servers are running "CentOS release 5.10 (Final)" and perl v5.8.8. (But the problem I'm running into appears to be a package management problem and not a Perl problem which is why I'm posting it to a CentOS list.) The line of code in the script that attempts to open a Net::SFTP connection, which was working fine on the old machine, no longer works on the new machine. I've tracked it down to the module Net::SSH::Perl::Key::DSA not loading correctly on the new machine. On the old one, the line: perl -e "use Net::SSH::Perl::Key::DSA;" gives no error and no output (as expected), but on the new machine, the same line gives: www:/var/www/html/circumventor# perl -e "use Net::SSH::Perl::Key::DSA;" Math::BigInt version 1.78 required--this is only version 1.77 at /usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA/KeyChain.pm line 4. BEGIN failed--compilation aborted at /usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA/KeyChain.pm line 4. Compilation failed in require at /usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA.pm line 7. BEGIN failed--compilation aborted at /usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA.pm line 7. Compilation failed in require at /usr/lib/perl5/vendor_perl/5.8.8/Net/SSH/Perl/Key/DSA.pm line 14. BEGIN failed--compilation aborted at /usr/lib/perl5/vendor_perl/5.8.8/Net/SSH/Perl/Key/DSA.pm line 14. Compilation failed in require at -e line 1. BEGIN failed--compilation aborted at -e line 1. I tried to install Math::BigInt on my new machine, by adding a file at /etc/yum.repos.d/custom.repo containing the lines: [local] name=Perl_module baseurl=http://apt.sw.be/redhat/el5/en/i386/rpmforge/ enabled=1 gpgcheck=0 and then running "yum install Math::BigInt", but it just goes through a lot of spew and then ends with this error: >>> Transaction Check Error: file /usr/share/man/man3/Math::BigFloat.3pm.gz from install of perl-Math-BigIn t-1.89-1.el5.rf.noarch conflicts with file from package perl-5.8.8-41.el5.i386 file /usr/share/man/man3/Math::BigInt.3pm.gz from install of perl-Math-BigInt- 1.89-1.el5.rf.noarch conflicts with file from package perl-5.8.8-41.el5.i386 file /usr/share/man/man3/Math::BigInt::Calc.3pm.gz from install of perl-Math-B igInt-1.89-1.el5.rf.noarch conflicts with file from package perl-5.8.8-41.el5.i3 86 file /usr/share/man/man3/Math::BigInt::CalcEmu.3pm.gz from install of perl-Mat h-BigInt-1.89-1.el5.rf.noarch conflicts with file from package perl-5.8.8-41.el5 .i386 Error Summary >>> Both servers have Math::BigInt 1.77 installed. As far as I can tell, the reason the error occurs on the new server but not on the old server, is because on the old server the place that Math::BigInt is loaded is in the file /usr/lib/perl5/vendor_perl/5.8.8/Net/IP.pm which contains the line: use Math::BigInt; whereas on the new server, Math::BigInt is loaded in the file /usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA/KeyChain.pm which contains the line: use Math::BigInt 1.78 try => 'GMP, Pari'; However, that's where my "expertise", such as it is, runs out. I have no idea why the two machines even attempt to load Math::BigInt in two different ways since I don't remember installing things differently on them. I would like to fix the problem on the new machine in the cleanest possible way (i.e., not just commenting out the "1.78" in the line "use Math::BigInt 1.78" -- I don't think that would be the "clean" solution!). Any idea what to do? Bennett