cpulimit: 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/cpulimit - from package: cpulimit

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

On Debian possible default full paths are:

/usr/bin/cpulimit - from package: cpulimit

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

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