polygraph-polyrrd: 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/polygraph-polyrrd - from package: polygraph

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

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