sbuild-distupgrade: 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/sbuild-distupgrade - from package: sbuild

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

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