The aliases are another nice feature on the advanced search. Many Web sites have multiple ways of writing a URL that will get to the exact same page, especially on the home page. The Aliases section of the advanced search gives three options. The default groups all host name aliases together, for the most comprehensive retrieval. However, a second option to "Show Aliases Separately" will give the exact matches for only the URL entered with a list of the other aliases while "Don't Show Aliases" will only give the exact matches.
Even with terabytes of data, there is a great deal missing. The Internet Archive only includes a small amount of material from , and the Web certainly pre-dates that. In addition, the older gopher content and other non-Web files are unavailable. More significant are the orchestrated exclusions.
Anyone can exclude their own pages by use of a robots. If the Internet Archive includes your Web pages and you want them excluded, just add a robots. The next time your page is crawled, all the old pages in the archive will be excluded as well. See www. Unfortunately, far too many sites have had a robots. At least when a user requests a page that has been excluded due to a robots. The archiving process does have some problems. Most images are archived, but some still point to the original source and, thus, may end up as dead links or changed image files.
Other images or objects on a Web page, especially at high traffic sites, may be linked to a network caching version, with a URL on an Akamai host, for example. Thus, some images on some pages will be missing. Nor will the Wayback Machine always be available. After it first launched, a message often appeared stating that due to a "higher than expected number of requests," the Wayback Machine was down. At other times, you may run across a "This Internet Archive site is currently down for maintenance" message.
Given the huge size of the archive, another concern is the long-term financial viability of the Wayback Machine. However, we do not yet have an indexed text search of the documents in the collection. The collection is a bit too large and complicated for that. We continue to work on it and should have a full text search soon. What type of machinery is used in the Internet Archive?
The Internet Archive is stored on dozens of slightly modified Hewlett Packard servers. The computers run on the FreeBSD operating system. Each computer has Mb of memory and can hold just over gigabytes of data on IDE disks. How do you archive dynamic pages? There are many different kinds of dynamic pages, some of which are easily stored in an archive and some of which fall apart completely. When a dynamic page renders standard html, the archive works beautifully. When a dynamic page contains forms, JavaScript, or other elements that require interaction with the originating host, the archive will not accurately reflect the original site's functionality.
If you look at our collection of archived sites, you will find some broken pages, missing graphics, and some sites that aren't archived at all. We have tried to create a complete archive, but have had difficulties with some sites.
Here are some things that make it difficult to archive a web site:. The Standard for Robot Exclusion SRE is a means by which web site owners can instruct automated systems not to crawl their sites. Web site owners can specify files or directories that are allowed or disallowed from a crawl, and they can even create specific rules for different automated crawlers.
All of this information is contained in a file called robots. While robots. In fact most web sites do not have a robots. You may want to retrieve files which aren't of a certain type e. If you also need errors files 40x and 50x codes or redirections files 30x codes , you can use the --all or -a flag and Wayback Machine Downloader will download them in addition of the OK files. It will also keep empty files that are removed by default.
It will just display the files to be downloaded with their snapshot timestamps and urls. The output format is JSON. It won't download anything. It's useful for debugging or to connect to another application. Specify the maximum number of snapshot pages to consider. Count an average of , snapshots per page. Use a bigger number if you want to download a very large website.
Specify the number of multiple files you want to download at the same time. Allows to speed up the download of a website significantly. Waybackpack is a command-line tool that lets you download the entire Wayback Machine archive for a given URL. For instance, to download every copy of the Department of Labor's homepage through which happens to be the first year the site was archived , you'd run:. Waypackback is written in pure Python, depends only on requests , and should work wherever Python works.
Should be compatible with both Python 2 and Python 3. Many thanks to the following users for catching bugs, fixing typos, and proposing useful features:. Skip to content. Star 2.
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