drbl-perl-functions: 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

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/share/drbl/sbin/drbl-perl-functions - from package: drbl

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