lwp-dump: 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/lwp-dump - from package: perl-libwww-perl

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

On Debian possible default full paths are:

/usr/bin/lwp-dump - from package: libwww-perl

You may install the required package with command apt-get install {package}

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