polygraph-pgl2acl: command not found

Have You tried accessing the binary with the full path?

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-pgl2acl - from package: polygraph

You may install the required package with command apt-get install {package}
Error in other languages:
polygraph-pgl2acl: bevel nie gevind nie
polygraph-pgl2acl: comandă negăsită
polygraph-pgl2acl: comando não encontrado
polygraph-pgl2acl: commande introuvable
polygraph-pgl2acl: command not found
polygraph-pgl2acl: käsku ei ole
polygraph-pgl2acl: không tìm thấy lệnh
polygraph-pgl2acl: komanda nerasta
polygraph-pgl2acl: Kommando nicht gefunden.
polygraph-pgl2acl: kommandot finns inte
polygraph-pgl2acl: komut yok
polygraph-pgl2acl: nie znaleziono polecenia
polygraph-pgl2acl: níor aimsíodh an t-ordú
polygraph-pgl2acl: no se encontró la orden
polygraph-pgl2acl: no s'ha trobat l'ordre
polygraph-pgl2acl: opdracht niet gevonden
polygraph-pgl2acl: parancs nem található
polygraph-pgl2acl: perintah tidak ditemukan
polygraph-pgl2acl: príkaz nenájdený
polygraph-pgl2acl: příkaz nenalezen
polygraph-pgl2acl: команда не найдена
polygraph-pgl2acl: командата не е открита
polygraph-pgl2acl: 命令找不到
polygraph-pgl2acl: コマンドが見つかりません