Bandwidth Limit Exceeded
Your server may notify you that your website is about to exceed its bandwidth limit.
The limit is set by the server admin, and needs to be increased if it reaches 80% or 90% before the end of the month, at which time it is reset to zero. Some hosting providers require payment for extra bandwidth.
Increased bandwidth usage is often a good thing – it means you’re getting more traffic. However, if that’s not reflected in the site stats, other factors need to be examined.
Bad bots will attempt to download the whole site, or crawl every corner of it repeatedly whilst ignoring the rules set for them in robots.txt. Yandex (Russia) and Baidu (China) are notorious for this, and are often banned.
Sometimes images and data on your site are hotlinked by other sites, effectively stealing both your content and your bandwidth.