IBMgtSim: 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/IBMgtSim - from package: ibutils

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

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