module_info: 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/module_info - from package: perl-Module-Info

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

On Debian possible default full paths are:

/usr/bin/module_info - from package: libmodule-info-perl

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

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