mongooplog: 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/mongooplog - from package: mongodb

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

On Debian possible default full paths are:

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

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

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