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Two days ago when I wanted to check my blog, I found that my blog was redirected automatically to the host homepage. At first, I considered about being hacked or some malicious manipulation from outside to my website.
Firstly, I tried to scan the entire content of the website with grep command for the name of the host to find page(s) that contain the link for redirection in order to remove. This method is really handy when the website is hacked and redirects to other sites. However, in my case the issue was different and I did not have any luck to find the link. In fact, there was no redirection like.
Secondly, I contacted with the host and asked them about the matter, they mentioned that when your website takes more than 10 percent CPU usage such issue will occur and automatically the website is redirected to homepage of the host to reduce the load of the system. They also assured me that the cause of this problem could be WordPress cache plugin or other types of scripts which impose CPU load to the system. The only given advise was that when the CPU load will drop, the website would be accessible. As a result, I waited 24 hours to see is my website is recovered or not.
After more than 24 hours, when I checked the website there was no change in redirection and still the website was redirected to host page. Luckily, I did have latest backup of the site and so I tried to recover the website to see what would happen. After recovery, the situation was the same with redirection and I was totally disappointed. In fact, whenever I uploaded index.html or index.php the website was redirected even if the content of the file was empty.
Finally, I decided to reload my account which could have cause to remove all sub domain, databases, emails and everything but since I had backup of all I reloaded my Cpanel and after recovering database, files and everything, now the website is working fine.
The cause of CPU load in my case was Dropbox auto back up plugin which was set to backup from the entire of website daily. If you set your Dropbox to automatically back up from your website daily, watch out about CPU load.
