xenstore-read: 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/sbin/xenstore-read - from package: xenstore-utils

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

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