stonith: 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

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/stonith - from package: cluster-glue

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