today our website has been down due to a DDOS attack.
We have improved our infrastructure including our license server to make it more reliable and safer.
We apologize for any inconvenience.
And we learned how these hackers bring down a site. The web site was running out of disk space but “df” showed a ton of free disk. We finally found that “df -i” showed that the file system on linux ran out of inodes. Then with “find / -xdev -printf ‘%h\n’ | sort | uniq -c | sort -k 1 -n” it showed that a single directory had more than 1.8M files, which happend to be the captcha directory for the forum.
Apparently the DDoS attack kept generating new captcha images until it ran out of nodes on the file system at 1.8M requests in a day or so.
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