cansniffer: 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/cansniffer - from package: can-utils

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

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