sha512: 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/sbin/sha512 - from package: hashalot

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

Error in other languages:
sha512: bevel nie gevind nie
sha512: comandă negăsită
sha512: comando não encontrado
sha512: commande introuvable
sha512: command not found
sha512: käsku ei ole
sha512: không tìm thấy lệnh
sha512: komanda nerasta
sha512: Kommando nicht gefunden.
sha512: kommandot finns inte
sha512: komut yok
sha512: nie znaleziono polecenia
sha512: níor aimsíodh an t-ordú
sha512: no se encontró la orden
sha512: no s'ha trobat l'ordre
sha512: opdracht niet gevonden
sha512: parancs nem található
sha512: perintah tidak ditemukan
sha512: príkaz nenájdený
sha512: příkaz nenalezen
sha512: команда не найдена
sha512: командата не е открита
sha512: 命令找不到
sha512: コマンドが見つかりません