ethstats: 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

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/ethstats - from package: ethstats

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