slony_logshipper: 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_logshipper - from package: slony1-2-bin

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

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