lbzdiff: 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/lbzdiff - from package: lbzip2-utils

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

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