pt-slave-restart: 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/pt-slave-restart - from package: percona-toolkit

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

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