paris-traceroute: 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/sbin/paris-traceroute - from package: paris-traceroute

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

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