Best practice for extra domains?

[Valiant]

So I have the following as my main site


www.my-site.co.uk

But I also have:
www.mysite.com
www.mysite.co.uk
www.my-site.com
etc

They are registered with one company and my sites are hosted elsewhere. If I do a simple domain redirect to the main site, do I do a 301 or 302? At the moment I was just doing a masked redirection but I just noticed that shows up with an insecure flag in the browser which isn't a good look.

[Pickled Onion]

I am by no means an expert, but I think it's certainly a 301. Both for the semantics (your site is permanently on your chosen main domain) and for search engines to list you as one site and not dilute any ranking points. The general advice seems to be to use 302 for redirects within the site, eg for out-of-stock items.

[Afasoas]

+1

Use 301 permanent redirect to the canonical URL