slave1: 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/slave1 - from package: pvm-examples

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

Error in other languages:
slave1: bevel nie gevind nie
slave1: comandă negăsită
slave1: comando não encontrado
slave1: commande introuvable
slave1: command not found
slave1: käsku ei ole
slave1: không tìm thấy lệnh
slave1: komanda nerasta
slave1: Kommando nicht gefunden.
slave1: kommandot finns inte
slave1: komut yok
slave1: nie znaleziono polecenia
slave1: níor aimsíodh an t-ordú
slave1: no se encontró la orden
slave1: no s'ha trobat l'ordre
slave1: opdracht niet gevonden
slave1: parancs nem található
slave1: perintah tidak ditemukan
slave1: príkaz nenájdený
slave1: příkaz nenalezen
slave1: команда не найдена
slave1: командата не е открита
slave1: 命令找不到
slave1: コマンドが見つかりません