simplevisor-loop: 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

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/simplevisor-loop - from package: python-simplevisor

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