wget

The wget command, which we will use extensively throughout this aide-memoire, downloads files using the HTTP/HTTPS and FTP protocols. The example below shows the use of wget along with the -O switch to save the destination file with a different name on the local machine:

wget -O report_wget.pdf https://www.offensive-security.com/reports/penetration-testing-sample-report-2013.pdf

Downloading a file with wget, renaming the local copy

Additional Options

wget has some other handy options that you should be familiar with.

Specifying an Output Directory

We can specify a directory to download a file to with the -P option:

wget -P /mnt/iso http://mirrors.mit.edu/centos/7/isos/x86_64/CentOS-7-x86_64-Minimal-1804.iso

Download Multiple Files

If you want to download multiple files at once, use the -i option, followed by the path to a local or external file containing a list of the URLs to be downloaded. Each URL needs to be on a separate line.

The following example shows how to download the Arch Linux, Debian, and Fedora iso files using the URLs specified in the linux-distros.txt file:

wget -i linux-distros.txt

http://mirrors.edge.kernel.org/archlinux/iso/2018.06.01/archlinux-2018.06.01-x86_64.iso
https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/debian-9.4.0-amd64-netinst.iso
https://download.fedoraproject.org/pub/fedora/linux/releases/28/Server/x86_64/iso/Fedora-Server-dvd-x86_64-28-1.1.iso

Resume a Download

We can also resume a download that has dropped off with -c:

wget -c http://releases.ubuntu.com/18.04/ubuntu-18.04-live-server-amd64.iso

If the remote server does not support resuming downloads, wget will start the download from the beginning and overwrite the existing file.

Download in the Background

We can also run downloads in the background with the -b option:

wget -b https://download.opensuse.org/tumbleweed/iso/openSUSE-Tumbleweed-DVD-x86_64-Current.iso

By default, the output is redirected to wget-log file in the current directory. To watch the status of the download, use the tail command:

$ tail -f wget-log

Change the User-Agent String

We can also manually change the User-Agent string so wget can appear as any browser when downloading a file via the --user-agent= option:

wget --user-agent="Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0" http://wget-forbidden.com/

Download a Local Copy of a Website

To create a mirror of a website with wget, use the -m option. This will create a complete local copy of the website by following and downloading all internal links as well as the website resources (JavaScript, CSS, Images):

wget -m https://example.com

If you want to use the downloaded website for local browsing, you will need to pass a few extra arguments to the command above:

wget -m -k -p https://example.com

The -k option will cause wget to convert the links in the downloaded documents to make them suitable for local viewing. The -p option will tell wget to download all necessary files for displaying the HTML page.

Skipping the SSL Certificate Check

If you want to download a file over HTTPS from a host that has an invalid SSL certificate, use the --no-check-certificate option:

wget --no-check-certificate https://domain-with-invalid-ss.com

Download to Standard Output (STDOUT)

In the following example, wget will quietly (-q) download and output the latest WordPress version to STDOUT(-O -) and pipe it to the tar utility, which will extract the archive to the /var/www directory.

wget -q -O - "http://wordpress.org/latest.tar.gz" | tar -xzf - -C /var/www