get_root_domain: 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/get_root_domain - from package: libdomain-publicsuffix-perl

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

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