showpart: command not found

Have You tried accessing the binary with the full path?

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/sbin/showpart - from package: anaconda

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