gsstool: 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/bin/gsstool - from package: heimdal-workstation

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

On Debian possible default full paths are:

/usr/bin/gsstool - from package: heimdal-clients

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

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