SPAM Deterrence
It seems there are many SPAM control and deterrence options out there for Drupal. Some are good, most dont seem to work too well. Letely, I have seen a number of our Kalacare sites under attack. After much trials and tribulations I have foind that this combo works the best hands down. It eliminates all SPAM:
USE THESE MODULES
Read the instructions on each module as each have different setup configs
- https://www.drupal.org/project/httpbl (gets about 80% of them)
- https://www.drupal.org/project/honeypot (enable on external facing forms. don't enable on node form as it will make editing the site hard sometimes)
- https://www.drupal.org/project/antibot (evaluating)
note that these solutions will turn caching off on pages where forms live.
For email obfuscation see: Email obfuscation
CAPTCHA OPTIONS
In one case out of many, it seemed the SPAM attacks were DDoS attemps. One site was getting over 100k hits per day on their forms. Although this method stopped all of them. The external calls to mollom crushed the site performance. There is not much you can do but enable New Relic, check the reports and most likely disable all forms on the site in a case like this until they go away.
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