update-smart-drivedb: 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 CentOS possible default full paths are:

/usr/sbin/update-smart-drivedb - from package: smartmontools

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/update-smart-drivedb - from package: smartmontools

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

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