SEO help for replacing a website - asp.net-mvc

Question

I run a small e-commerce site that over the last few years has built up a reasonable search engine status.
I've been working on a new site that uses new URL formats and I am worried about how to deal with all the broken links and customer frustration for users finding out dated links through search engines.
Can anyone offer advice on how to mitigate / minimize the damage? The old site was done in ASP.NET the new in ASP.NET MVC
Thanks for any help you can be.

Answer 1

You will need some sort of parallel structure. Ideally, the old site with the old URLs remains fully accessible for some time, but does not get indexed any more.
If that's not feasible, and since you are saying that the site is small, you could establish a URL mapping old-new and have a 404 handler that attempts to redirect to the new content.

Answer 2

You should create permanent redirects for the links you want to preserve (routelevel). This way searchengines will update their references to the new locations.

Answer 3

As cdonner says, you want to have a handler that reroutes the traffic to its appropriate destination. Even more important though, is you want to make sure when you redirect the client, you send a status code of 301 (permanently moved) instead of 404. The search engines will rate you negatively if there are a lot of 404 errors on your site and you will see your standing decrease instead of increase.

Answer 4

You could set up your old site's .htaccess file to redirect traffic to the new site. Beyond that, you could use mod_rewrite to map requests to pages on the old site to the same (or similar) pages on the new one.

Answer 5

This is the way I do it migrating from an old ASP classic site:
Sub Application_BeginRequest(ByVal sender As Object, ByVal e As System.EventArgs)
Dim fullOriginalpath As String = Request.Url.ToString.ToLower
If (fullOriginalpath.Contains("/viewitem.asp?itemid=")) Then
Context.Response.StatusCode = 301
Context.Response.Redirect("/item/" + getItemIDFromPath(fullOriginalpath))
ElseIf (fullOriginalpath.Contains("/search.asp")) Then
Context.Response.StatusCode = 301
Context.Response.Redirect("/search/")
ElseIf (fullOriginalpath.EndsWith("/default.asp")) Then
Context.Response.StatusCode = 301
Context.Response.Redirect("/")
End If
End Sub

Answer 6

Sounds like you have it figured out, but just wanted to add one more option - the canonical tag - which may have advantages if for any reason you needed to keep both the old url and the new URL active. You can create a copy of the page at the old URL and then add the "canonical" tag, which tells the search engines "please credit the link credits of this page to the following page: www.site.com/newpage"
<link rel="canonical" href="http://www.yoursite.com" /> this line goes in before </head>
For example if you have lots of links to certain key pages and those links are pointed to the old URL's, this may be a help.
A 301 also redirects the link credits, and generally moved pages you'll want to use a 301 redirect. Oh and if you use a URL rewrite rule and all the URL's change in the same way, you can probably use regex in the rewrite rule to handle all of them in a single step.