all-knowing-dns: 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/all-knowing-dns - from package: all-knowing-dns

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

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