mknmz: 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 Debian possible default full paths are:

/usr/bin/mknmz - from package: namazu2-index-tools

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

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