I host a network of service websites that consists of 1 main website and several mirrored websites under different domains; think torrent, proxy, or download sites. Users come to my service but there is a possibility that my main domain is blocked by their internet service provider or some sort of school or work filter. Therefore the service I offer is available from many different domains and IP addresses.
My main site has all unique content and proper SEO while all of the mirror sites share the same content which is different from the main site to avoid duplicate content issues for the main site.
My main site is indexed and ranked well in search engines while my mirror sites are not. I have no intention for the mirrors sites to ever get ranked they are only provided as a means to be able to access my service if the main domain is inaccessible.
I like to place links to my main site from all of my mirror sites.
My question is should I use
rel="nofollow" on all of my mirror sites? I am thinking I should because the quality of the mirror sites are very low and I don't want it to seem like a link scheme. I only want these links there as a means to let the user know that the service is provided as part of the main site; I have no intention to try and falsely inflate backlinks.
If that question is too broad or website specific then I ask the following: Will using
rel="nofollow" negate any negative effects from low quality links to a website.