Help understanding 301 domain redirect

[gazzerman1]

Can anyone help me understand a specific process of a 301 redirecting a domain.

Here is what I would like to know....

When you 301 redirect a site, most if not all the links follow to your new site. But how does this process happen?

1.When Google sees the new domain does it simply apply the backlink profile of the old site to the new one?

2. Does it have to re-crawl all the links one by one and apply them to the new domain?

3. or something else?

[GPainter]

Matt Cutts touches on it here:

http://www.youtube.com/watch?v=Filv4pP-1nw

A 301 is telling Google that the new home of that link is there.

I've seen whole sites 301 then the site has ranked a bit of the keyword that was not relevant to the site (e.g batteries to a site than doesn't sell anything).

I would assume your link would have to be re-crwaled so Google knows the new home once it has been though it shouldn't need to re do it.

in short:Google finds the 301 then knows  that is the new home of the link and passes anything that used to go to that link onto the new location.

I hope that helps a bit for you. If not I'm sure some one around here can go far more in depth if you want it more technical

[gazzerman1]

Hi Chris,thanks for the response.

However you say "I would assume your link would have to be re-crawled" and that is the only bit I needed a definitive answer for LOL.

I have looked everywhere for an answer but so far not found one....

[GPainter]

I know you can submit your site in webmaster tools to be re-crawl if  you need it to be re-crawled.

I can only think it must re-crawl it to find the new location its pointed to.

Sorry I couldn't give you a definitive answer, good luck though.

[Paddy_Moogan]

Hi Gary,

To answer each of your questions:

1. Unfortunately, it isn't that simple. There are a few factors that Google will take into account when it sees 301 redirects to a new domain. In the past, this technique has been used to manipulate Google, for example people would buy expiring domains that have links pointing to them, then 301 that domain to their own - even if the domain was in no way related to what the expired domain was about. So Google will look at the relevancy of the links and try to figure out if the redirects would make a good user experience for anyone who clicks on the links and gets redirected.

2. Yes. Google needs to crawl the links in order to find the redirect and see where it points to. Depending on how strong your website is in terms of link equity, it may take a few hours to a few weeks for Google to crawl all of the pages on your site and find the redirects. Because of this, redirecting one site to another can often lead to at least a temporary loss in traffic for the domain whilst Google figures out what is going on.

I hope that helps!

Paddy