monmaptool: 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/monmaptool - from package: ceph

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

On Debian possible default full paths are:

/usr/bin/monmaptool - from package: ceph

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

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