asterisk-dump: 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 Debian possible default full paths are:

/usr/bin/asterisk-dump - from package: python-asterisk

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

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