rsysinfo: 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 Debian possible default full paths are:

/usr/bin/rsysinfo - from package: rstat-client

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

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