charon-cmd: 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/sbin/charon-cmd - from package: strongswan

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

On Debian possible default full paths are:

/usr/sbin/charon-cmd - from package: charon-cmd

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

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