csync2-compare: 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-compare - from package: csync2

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

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