rpcdebug: 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 CentOS possible default full paths are:

/usr/sbin/rpcdebug - from package: nfs-utils

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/rpcdebug - from package: nfs-common

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