drbl-gen-ssi-files: 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/share/drbl/sbin/drbl-gen-ssi-files - from package: drbl

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

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