ctl_cyrusdb: 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/lib/cyrus/bin/ctl_cyrusdb - from package: cyrus-common

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

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