openscada_start: 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/bin/openscada_start - from package: openscada

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

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