kramdown-rfc2629: 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/kramdown-rfc2629 - from package: ruby-kramdown-rfc2629

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

Error in other languages:
kramdown-rfc2629: bevel nie gevind nie
kramdown-rfc2629: comandă negăsită
kramdown-rfc2629: comando não encontrado
kramdown-rfc2629: commande introuvable
kramdown-rfc2629: command not found
kramdown-rfc2629: käsku ei ole
kramdown-rfc2629: không tìm thấy lệnh
kramdown-rfc2629: komanda nerasta
kramdown-rfc2629: Kommando nicht gefunden.
kramdown-rfc2629: kommandot finns inte
kramdown-rfc2629: komut yok
kramdown-rfc2629: nie znaleziono polecenia
kramdown-rfc2629: níor aimsíodh an t-ordú
kramdown-rfc2629: no se encontró la orden
kramdown-rfc2629: no s'ha trobat l'ordre
kramdown-rfc2629: opdracht niet gevonden
kramdown-rfc2629: parancs nem található
kramdown-rfc2629: perintah tidak ditemukan
kramdown-rfc2629: príkaz nenájdený
kramdown-rfc2629: příkaz nenalezen
kramdown-rfc2629: команда не найдена
kramdown-rfc2629: командата не е открита
kramdown-rfc2629: 命令找不到
kramdown-rfc2629: コマンドが見つかりません