frsg: 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 Debian possible default full paths are:

/usr/bin/frsg - from package: pvm-examples

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