scl: 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
/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/scl - from package: scl-utils

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