yasr: 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/yasr - from package: yasr

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

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