bannergrab: 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/bannergrab - from package: bannergrab

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

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