umockdev-run: 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/umockdev-run - from package: umockdev

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

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