jx_openmpi: 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/lib64/openmpi/bin/jx_openmpi - from package: openmx-openmpi

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

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