dnsproxy: command not found

Have You tried accessing the binary with the full path?

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/sbin/dnsproxy - from package: dnsproxy

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