swift-proxy-server: 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/swift-proxy-server - from package: swift-proxy

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

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