Checking links on a web page should be a part of a regular maintenance routine for a Web site. You should use a two step process for validating links on a site:
- Check links using an automated tool
- Check links manually/visually
Step 1 - Check links using a Link Checker Tool
On a regular basis, use an automated tool for checking to see if links are still working.
The partial list of link checker tools listed below can be used to assist in checking for dead links (this information was posted in April '07; ITS does not provide support for these tools nor endorse or promote them; please select and consider a tool that best fits your needs; these are off-campus external links):
Single Page Link Checking Tool:
- Linkchecker - Firefox add-ons - checks one web page at a time, highlights links using color coding. Installs as an add-on to your Firefox Web browser.
- W3C Link Checker - an online link checker: very thorough and produces an easy to read report (at the bottom of the page). Be patient as it's a bit slow if there's many links on a page.
Whole Site Link Checking Tools:
- Deep Trawl – for purchase, a highly comprehensive link checking tool which checks for profanity, outdated material, HTML coding flaws, and can be left unattended to performed timed link checks. This program has a very easy to use interface and provides its results in very easy-to-follow reports.
- Inspyder InSite – for purchase, a very easy to use link checking tool that provides clean reports. This tool also has the ability to take a starting page (as well as other limiting criteria) and crawl your entire site for broken links. Furthermore, this program also checks your website for spelling errors which can be edited through custom dictionaries.
- Xenu - a freeware tool that provides excellent results. Don't let the martian graphic fool you, Xenu can find problem links that other link checkers don't. We like this tool because you can submit a text list of URLs to check.
Step 2 - Perform Manual Link Check for Content Integrity
Periodically perform a manual check of the links on each of your web pages, visually checking to ensure that each link correlates with the content of the linked web site. This is important because the content of a linked Web site could change to the extent that it no longer reflects the purpose and text of the link on your site.
Removing Pages from your Web site (or moving an entire site)
When you move an entire campus Web site or rename, move or delete pages from a Web site, most often links from other campus Web sites will break. It is the responsibility of the campus Web site owner to determine which campus Web sites have links to the pages that have been changed, then notify the owners of the Web sites that they need to update their links. The following procedure will assist with this process.
Step 1 - Delete links and content from old pages (and leave them in place)
- In your web editor software (e.g. Dreamweaver, BBEdit), delete all links and text within the page you are removing/redirecting. The idea is to remove content from the page so that it's not duplicated with a newer page or picked up by a search engine. Also, this is the first step in creating a page that will be left behind so that when a user clicks on a link on another web site that hasn't been updated, that they will be properly referred to the new page/site.
Step 2 - Make this page a "Referrer" page.
A "Referrer" page is left in place of an old page to serve as a way to direct a user to the new content should they somehow end up on the old page. Referrer pages should be left in place for three months to a year.
The following explains how to make a "Referrer" page
- Change the page <title> to indicate the page has been moved (e.g. The Systems & Facilities page has been moved). In Dreamweaver the title text is changed through the Title: input box at the top of the page when in editing mode.
- Remove or change any headers or relevant graphics to show the page is not in use anymore (similar to Step 1 only pay attention to the header or title of page contents).
- Place Referrer text and a link to the new web page (e.g. "The Computing Resources page has been moved to the ITS web site"). The referrer text tells a user that the page content has been moved to the new (linked) location. Leave a brief statement with the new link stating that this is where the new page is located.
- Upload this new Referrer page to your site.
Step 3 - Notify other sites, that are linked to your page, to change their links to your new page
- Go to http://www.cpsearch.calpoly.edu/.
- Click on Advanced Search.
- At the bottom of the page in the Page-Specific Search section, copy your old link into the form area and click on Search. You may need to use several derivatives of your URL, for example http://www.dept.calpoly.edu and http://dept.calpoly.edu/
OR type "link:URL" (e.g. link:http://www.calpoly.edu) into a regular campus Google Search. This gets you the same results.
- The search results are other sites that contain a link(s) to your old page.
- Go to every Web site that the Google search displays.
- For each Web site that the Google Search displays, find where the link to your page is and any contact info so you can send out an e-mail notification to that person/company.
Step 4 - Develop e-mail notification to users of your old link
- Make a standard e-mail text to send out to all the users linked to your old site (view sample Standard e-mail Text).
- Fill in the italicized text areas with the relevant links and text.
- Send out individual e-mails to all contacts.
Step 5 - Follow up on any responded e-mails sent from the persons you contacted.
Standard e-mail Text - copy and paste this text and make the appropriate edits:
This message is from [your name].
The following Web page that you may own contains a link to a Web page that has been moved/deleted/renamed.
Your Web page: [copy and paste the URL]
This is the text and link on your Web page: [place the Text and URL]
The new Web page to link to: [copy and paste the new URL you made]
If you have any questions or concerns, please don't hesitate to write back.
Your Name, email Address, Phone Number, etc.
Step 6 - Submit your site URL to Commercial Google for re-indexing
In order to help keep the campus web presence relevant and accurate to the greater web community outside of the campus, you should submit your URL to commercial Google whenever you make changes to your site structure, including complete removal of the site.
- Go to http://www.google.com/addurl/ and submit your URL even if the site has been deleted from the Cal Poly Web space.