nodeunit: 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/nodeunit - from package: nodeunit
/usr/lib/node_modules/nodeunit/bin/nodeunit - from package: nodeunit

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

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