问题
If i have a page ("dontFollowMe.html") with the meta tag:
< meta name = "robots" content = "noindex, nofollow" / >
... and I link to that page ...
Do I need to include the nofollow rel attribute to the a element? :
<a href="dontFollowMe.html" rel="nofollow">sign in</a>
Thanks
回答1:
No, you don't necessarily need to use nofollow on a page that is noindexed (for technical reasons, as your question described).
nofollow = "Do not pass link juice to this page. Just pretend it doesn't exist". Of course, this is just a suggestion to the search engines.
noindex = "Do not index this page. I don't care whether other pages linked to it as followable or not, just don't index it."
For SEO reasons: if this question is assuming you're linking to an internal page, then the answer to your question would be that typically you would want to nofollow the link to this unimportant page and also noindex it on the unimportant page.
回答2:
rel="nofollow" will signal crawlers to not to follow the links. If you want spiders to spend quality time on other links on the page, you typically add rel="nofollow" to the links that you do not want it to be crawled. Other reason would be if you cannot vouch for what is there in the linked page. Having "no follow" on the page signals no to follow any outgoing links on the page. Page would still be crawled by crawler by google.
回答3:
(As you tagged your question with a googlebot tag, I assume your interest is in Google and the nofollow tag and link attribute.)
If you have nofollow as a meta tag, then you do not need to add to individual links, because :
The nofollow robots meta tag applies to all links on a page. The rel="nofollow" link attribute only applies to specific links on a page. For more information on the rel="nofollow" link attribute, please see our Help Center articles on user-generated spam and the rel="nofollow".
How does the nofollow robots meta tag compare to the rel="nofollow" link attribute?
回答4:
nofollow as value of meta-robots and nofollow as link type mean different things, or exactly the same, depending on which definition you follow (details).
HTML5 defines that the link type nofollow
[…] indicates that the link is not endorsed by the original author or publisher of the page, or that the link to the referenced document was included primarily because of a commercial relationship between people affiliated with the two pages.
It does not mean that the link should/must not be followed by visitors/bots.
So unless you do not endorse the link to your dontFollowMe.html, or unless you have only added it for commercial reasons (i.e., advertisement), you should not use the nofollow link type.
来源：https://stackoverflow.com/questions/28371530/do-i-need-to-add-nofollow-rel-attribute-to-links-if-the-href-page-contains-a-rob