ptpd2: 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 CentOS possible default full paths are:

/usr/bin/ptpd2 - from package: ptpd

You may install the required package with command yum install {package}

Error in other languages:
ptpd2: bevel nie gevind nie
ptpd2: comandă negăsită
ptpd2: comando não encontrado
ptpd2: commande introuvable
ptpd2: command not found
ptpd2: käsku ei ole
ptpd2: không tìm thấy lệnh
ptpd2: komanda nerasta
ptpd2: Kommando nicht gefunden.
ptpd2: kommandot finns inte
ptpd2: komut yok
ptpd2: nie znaleziono polecenia
ptpd2: níor aimsíodh an t-ordú
ptpd2: no se encontró la orden
ptpd2: no s'ha trobat l'ordre
ptpd2: opdracht niet gevonden
ptpd2: parancs nem található
ptpd2: perintah tidak ditemukan
ptpd2: príkaz nenájdený
ptpd2: příkaz nenalezen
ptpd2: команда не найдена
ptpd2: командата не е открита
ptpd2: 命令找不到
ptpd2: コマンドが見つかりません