ndrdump: 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/ndrdump - from package: samba4-test

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

On Debian possible default full paths are:

/usr/bin/ndrdump - from package: samba-testsuite

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

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