wol: 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/wol - from package: wol

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

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