cleanarch: 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/cleanarch - from package: dnssec-tools
/usr/lib/mailman/bin/cleanarch - from package: mailman

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

On Debian possible default full paths are:

/usr/lib/mailman/bin/cleanarch - from package: mailman

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

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