rpc.gssd: 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 CentOS possible default full paths are:

/usr/sbin/rpc.gssd - from package: nfs-utils

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

On Debian possible default full paths are:

/usr/sbin/rpc.gssd - from package: nfs-common

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

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