grunt-cli: 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/grunt-cli/bin/grunt-cli - from package: nodejs-grunt-cli

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

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