DNN 6.01, IIS 7, SQL Server 2008, Server 2008 R2

Single website. Default alias is IP address. Created separate aliases 3 years ago for sitename.com and www.sitename.com. No problems whatsoever until a few days ago and no changes to server or DNN environment preceding the problem.

Every several hours the host stops processing page requests using the proper sitename alias. The environment and site are up and running. You can access the site from its IP, just not any legit alias. Confirmed that it's not a DNS or domain registrar problem. Everything there is fine, stable, unchanged. Also not a firewall problem.

Rebooting the server resolves the problem for a few hours until next occurrence. Restarting the host environment/application and restarting the website have no impact.

When I look at the SQL tables I see the aliases exactly as they should be.

Now a separate but possibly related problem. To make matters worse, all the SEO work I put into this site 4 years ago is no longer being recognized by Google. All the standard SEO fields were properly completed long ago. The Google Analytics account is in place. The tracking code is in place. The site was seeing excellent results for over 2 years. Now when you type keywords into Google that have returned top 10 organic rankings in the past, nothing. Two bizarre problems for the price of one.

I'm running separate DNN 6.2.9 and DNN 7.x environments on the same server and none of the above problems.

Any guidance or advice would be greatly appreciated.

 Thanks,

 Fred