cyrus: 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/sbin/cyrus - from package: cyrus-common

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

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