sigul_setup_client: 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/bin/sigul_setup_client - from package: sigul

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

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