I have no idea how big the RBL mirror is, but I do know that it takes about 200 MB to do 1,000,000 DNS queries.
Keith -----Original Message----- From: Hans du Plooy [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 26, 2004 11:27 AM To: [EMAIL PROTECTED] Subject: Re: RBL mirror On Wednesday 26 May 2004 15:29, Rick Macdougall wrote: > > Also, in terms of bandwidth usage, how much mail does spamassassin > > need to process (and check against DNS and RBL) before mirroring > > RBLs locally become economic? Obviously for our office with 6 > > people this would be a waste, but I'm considering this for bigger > > clients. > > Hi, > > Anytime you mirror the RBL's locally, you will see a time improvement > on processing. Thanks for your response. The issue here for me is not really the time it takes, but the bandwidth used. A lot of our clients run on ADSL connections. ADSL here (in South Africa) have a bandwidth limit of 3gb per month, after which international bandwith is capped (i.e. moved to a 64k line shared by all capped users), rendering it pretty much unusable. Anything that would save bandwidth is worth looking into. I just don't know how to calculate or measure how much bandwidth we're using on RBL and DNS checks. I'm trying to find the point where bandwidth used for DNS and RBL checking for x number of mails is equal to bandwidth used to mirror the specified RBLs. Running DNS locally would of course cut down on bandwidth, regardless (correct me if I'm wrong). What would be preferable, considering the connection is used for other things as well: local DNS cache or running bind locally? Also, it was mentioned that bind needs lots of memory. Is that true for a dns cache too? How much? We usually have at least a dual Xeon with 1gb RAM available. Thank you -- Kind regards Hans du Plooy Newington Consulting Services hansdp at newingtoncs dot co dot za ***** The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential, proprietary, and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from all computers. 113
