问题
I have a network of about 200 blogs (Wordpress Multisite), and all of them show links to all the other ones on a sidebar on the right hand side (basically 200+ links on the right hand side of every single page). I have it set to rel="nofollow" now, but I was wondering if changing it to rel="noindex, nofollow" would be a good idea?
Thank you for any input.
回答1:
nofollow
nofollow only means that a bot should not follow this link. If you are concerned only about Google (as your tag suggests) this will probably be of help:
How does Google handle nofollowed links?
In general, we don't follow them. This means that Google does not transfer PageRank or anchor text across these links. Essentially, using nofollow causes us to drop the target links from our overall graph of the web. However, the target pages may still appear in our index if other sites link to them without using nofollow, or if the URLs are submitted to Google in a Sitemap. Also, it's important to note that other search engines may handle nofollow in slightly different ways. [Source]
However, adding this attribute is in no way a hard restriction, there is no standard, and some bots may ignore it altogether. Also, search engines may still flag the page as a linkbuilding site depending on content/link ratio.
noindex
noindex is not used in links by Google (I do not know about others). It is meant for the robots <meta> attribute in the html header and applies to the whole page. So it is most likely no use for you. Example:
<meta name="robots" content="noindex"/>
linkbuilding
200 links are however not very user-friendly either. You should seriously consider reducing the number of links by (for example) selecting those that have a similar topic.
As you read this, look to the right, yes, here on Stack Overflow, there is a "Box" titled Related. This is how you do it. Imagine them putting every single topic ever created in there... Not very useful.
Also if you do this with some logic like I suggested above and not just randomly selecting N links from the list, you can probably remove the nofollow, since the links will become useful and Google likes useful links.
You could then also add a "spotlight" for low-traffic sites (those would probably need the nofollow though)
来源：https://stackoverflow.com/questions/13085931/is-it-a-good-idea-to-use-a-href-http-name-com-rel-noindex-nofollowname