cpan2dist: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/cpan2dist - from package: perl-CPANPLUS

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/cpan2dist - from package: libcpanplus-perl

You may install the required package with command apt-get install {package}

Error in other languages:
cpan2dist: bevel nie gevind nie
cpan2dist: comandă negăsită
cpan2dist: comando não encontrado
cpan2dist: commande introuvable
cpan2dist: command not found
cpan2dist: käsku ei ole
cpan2dist: không tìm thấy lệnh
cpan2dist: komanda nerasta
cpan2dist: Kommando nicht gefunden.
cpan2dist: kommandot finns inte
cpan2dist: komut yok
cpan2dist: nie znaleziono polecenia
cpan2dist: níor aimsíodh an t-ordú
cpan2dist: no se encontró la orden
cpan2dist: no s'ha trobat l'ordre
cpan2dist: opdracht niet gevonden
cpan2dist: parancs nem található
cpan2dist: perintah tidak ditemukan
cpan2dist: príkaz nenájdený
cpan2dist: příkaz nenalezen
cpan2dist: команда не найдена
cpan2dist: командата не е открита
cpan2dist: 命令找不到
cpan2dist: コマンドが見つかりません