mdump: 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/mdump - from package: med-tools

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

On Debian possible default full paths are:

/usr/bin/mdump - from package: libmed-tools

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

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