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Is it possible for your server to get hacked when you have VPS? How do you know when this has happened?
Yes it is possible
How to know if your VPS has been hacked? you can see the symptoms from your website behavior. such as;
1. Google says "This site may harm your computer"
2. Visitors report getting viruses from your web pages
3. Visitors report being redirected to other websites
4. Your traffic decreases dramatically and suddenly
5. Your files contain code you didn't put there
6. Your search engine result page (SERP) listings suddenly change