mongofiles: 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/mongofiles - from package: mongodb

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

On Debian possible default full paths are:

/usr/bin/mongofiles - from package: mongodb-clients

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

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