nebulaclient: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/bin/nebulaclient - from package: nebula

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