How to spot bad link exchanges

by PhilC

When considering exchanging links with another site, make sure that the other site is offering you a crawlable and beneficial link; i.e. a link that can be crawled by spiders that actually links to your site. If the link isn't crawlable or beneficial, you won't get any search engine benefit from it. To find out if a link is going to be crawlable and beneficial, look at the other links on the other site's page.


Non-crawlable/non-beneficial links are:-



Links that are written in Javascript.
e.g. <a href="javasacript:goto('http://www.yoursite.com/')">


Links that point to their site. The URLs contain information about where the visitor should be sent - your site.
e.g. <a href="/goto.php?target=www.yoursite.com">


Links that contain the "rel=nofollow" attribute.
e.g. <a href="http://www.yoursite.com" rel="nofollow">


Links on a page that cannot be found by spiders because there is no links path to it from the main site. For this, you need to look for the link path to the page, and check each link along the way to make sure that it is crawlable. Doing a "link:" search (link:www.theirdomain.com/whatever/linkspage.html) should show which page(s) link to the page. Also, searching on the page URL itself will show whether or not it is a search engine's index. But still check the path yourself. The start of the path should be the front page of the site.


Links on pages that are disallowed by the robotos.txt file. You can view any site's robots.txt file by typing its URL into the browser (www.domain.com/robots.txt). That must be the URL of the robots.txt file. If nothing is returned, then the site doesn't have a robots.txt file. Get the full path to the links page before checking the robots.txt file, because if any directory in the path is disallowed in the robots.txt file, everything in and under it, such as the links page, is also disallowed.


Links on pages that have the "noindex" or "nofollow" meta tag in the Head section:- <meta name="robots" content="noindex,nofollow">. If the "content" contains either of the words, noindex and nofollow, the links will be useless.


Links that are on cloaked pages. When a page is cloaked, the search engines see one version and people see another. A link can look perfectly good in every respect, but the search engines never see it because they get a different page. Check the engine's cache and compare what the engine has with the actual page.


Links that are contained in inline frames (the "iframe" tag). Google follows the sources of frames, but it doesn't follow iframe sources. So the links on the links page must not be displayed in an iframe, or Google, and maybe other engines, will never see them. iframes are not always obvious, so the source code must be checked. As an example, the Google AdSense ads on this page are displayed in an iframe, and are not part of the page's source code.


Notes:

When checking the other site's links page, look at the source code and don't rely on what the Status bar shows - see fambi's post below.

It's a good policy to periodically check your links from other sites, as it is not unknown for people to add the link initially, and then remove it or cheat a little later.

If you know any other methods of cheating, please let me know and I'll add them to the list.