slony_show_configuration: 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/slony_show_configuration - from package: slony1-2-bin

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

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