Images should also be redirected during a website migration
John answered a question about organic search fluctuations after a migration. As well as checking the page differences before and after in regards to aspects like internal linking, content or structure, it’s also important to consider embedded content like images.
If you don’t redirect your old image URLs, Google needs to reprocess them again and will find them again as new because they don’t have the connection between the old and the new URL ones. He clarified that it can have a big effect if you have a lot of image search traffic. It makes sense to set up those redirects even if you’ve moved over a month or so ago.
Internal URL changes can cause organic search fluctuations
A participant was seeing organic search fluctuations after a URL structure change on their website, despite adding 301 redirects. They asked if that is expected and how long the process should take. John responded that changing internal URLs means they have to almost reprocess the entire website and understand the context of all the pages on the website first, which can take a significant amount of time.
You are likely to see fluctuations in organic search for at least a month or longer if it’s a bigger change. Fluctuations can also occur if other changes have also happened at the same time, such as internal linking, content, or page structure updates which could have caused the pages to become weaker. If this is the case, John recommended reviewing the pages before and after to understand these differences and which things might need clearing up.
Crawl rate is not affected by a large number of 304 responses
A question was asked about whether a large number of 304 responses could affect crawling. John replied that if a 304 is encountered, it means that Googlebot could reuse that request and crawl something else on the website and that it would not affect the crawl budget. If most pages on a website return a 304, it wouldn’t mean that the crawl rate would be reduced, just that the focus would be on the pages of the website where they see updates happening.
There is no negative SEO effect from 302 redirects
A question was asked about whether 302 redirects pass link equity, or if there are any other issues which mean they should be avoided. John said there is no negative SEO effect from 302 redirects. He explained there is no hidden SEO benefit of one redirect type over the other, but they serve different purposes. With a 301 redirect, you want Google systems to pick up the destination page. With a 302, you want Google to keep the original URL as it is only a temporary change. If it’s purely about tracking the ranking of individual URLs, then a 301 will cause the destination page to be indexed and ranking, and a 302 will keep the original indexed and ranking.
Long-term 302 redirects are eventually treated as 301 redirects
If you have 302 redirects in the long term, eventually Google will treat them the same as 301 redirects. John mentioned that if implementing 301 redirects is an issue, then 302 redirects could be an option as they work the same as normal redirects and still pass PageRank.
It can take years for crawling on migrated domains to be stopped completely
John confirmed that it takes a very long time (even years) for the Google systems to completely stop crawling a domain, even after they are redirected.
Domain Redirects Should Remain in Place Permanently
Google recommends that domain redirects should remain in place for a significant amount of time, at least a year, but it’s better to keep it in place as long as possible whilst you’re still seeing users or bots accessing the old domain.
Google Follows More than 5 Redirects In Separate Crawl Cycles
Google follows a 5 redirects during one crawl cycle, but they will continue following the redirect chains later. Once they find the final URL in the redirect chain, they will focus on that URL.
Use 301 Redirects to Inform Google of Your Preferred URL Structure
If you have a mixture of www. and non www. URLs on a site, the best way to inform Google of your preferred URL structure is to add 301 redirects with a consistent preferred domain choice.