ronn.js: 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/lib/node_modules/ronn/bin/ronn.js - from package: nodejs-ronn

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

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