On Thu, Dec 8, 2011 at 8:42 PM, Sam Berry <samkbe...@googlemail.com> wrote: > Hello there, > > I am currently running a number of small sites using logging via email > to notify me of 404s and server errors. The volume of email produced > is perfectly manageable due to the low level of traffic.
First off, I'd point out that the 404 emails aren't sent every time your server generates a 404 -- they're only generated as a result of a 404 *from an internal link on your site*. If John Q Hacker hits http://yoursite.com/this_page_doesnt_exist, you won't get a 404 email. If you're getting *any* 404 emails, it means there are internal links on your site that don't resolve. If this is something that is happening systematically, at a rate that has given you cause for concern about the potential for DOS, I'd suggest you have a bigger problem with your site. > It does occur to me that it would be very easy to disrupt the site by > simply sending repeated requests which trigger a 404 Not Found. I'm > sure 10 404s a second would completely shutdown the process to normal > requests due to the time taken to send the log emails. I'm not using a > message queueing system. > > I would like to keep the option of receiving logging emails. Is there > anything I can do to throttle or limit the email sending without > writing my own logging handler? Interestingly, 404 emails aren't handled by a logging handler (unlike 500 messages) -- they're handled as a direct mail to site managers. This is something that is probably worth a ticket in itself; using the logging framework for 404 mails would allow for much more flexibility. So - what you want here isn't a custom logging handler, but a custom *mail* handler -- django-mailer [1] is a good candidate here. This makes "sending" an email a very short lived operation from the perspective of your web server -- all the web request does is queue the email for sending. The actual sending of mail is handled out of the request-response cycle. This removes the possibility of "DOS attack by 404" because the expensive operation is taken out of the request-response cycle. Of course, you could still end up being flooded with email -- so you either need to (a) monitor the size of your mail queue to make sure it isn't getting flooded, or (b) put a processor in place to merge/throttle the contents of the mail queue. This could also be handled with a custom mail handler; however, I can't point you at a ready-to-use candidate for this. Another option is to use a mechanism other than the 404 emails to log and handle errors. Django-sentry [2] and Arecibo [3] are two candidates here, both of which are easy to install, and provide much richer analytics than a full mailbox :-) [1] https://github.com/jtauber/django-mailer/ [2] https://github.com/dcramer/django-sentry/ [3] http://areciboapp.com/ Yours, Russ Magee %-) -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
