ibmonitor: 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/ibmonitor - from package: ibmonitor

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

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