csync2: 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/csync2 - from package: csync2

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

On Debian possible default full paths are:

/usr/sbin/csync2 - from package: csync2

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

Error in other languages:
csync2: bevel nie gevind nie
csync2: comandă negăsită
csync2: comando não encontrado
csync2: commande introuvable
csync2: command not found
csync2: käsku ei ole
csync2: không tìm thấy lệnh
csync2: komanda nerasta
csync2: Kommando nicht gefunden.
csync2: kommandot finns inte
csync2: komut yok
csync2: nie znaleziono polecenia
csync2: níor aimsíodh an t-ordú
csync2: no se encontró la orden
csync2: no s'ha trobat l'ordre
csync2: opdracht niet gevonden
csync2: parancs nem található
csync2: perintah tidak ditemukan
csync2: príkaz nenájdený
csync2: příkaz nenalezen
csync2: команда не найдена
csync2: командата не е открита
csync2: 命令找不到
csync2: コマンドが見つかりません