drblsrv-offline: 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/sbin/drblsrv-offline - from package: drbl

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

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