node-gyp: 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/node-gyp - from package: node-gyp
/usr/lib/node_modules/npm/bin/node-gyp-bin/node-gyp - from package: npm

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

On Debian possible default full paths are:

/usr/bin/node-gyp - from package: node-gyp

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

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