RBL performance: caching nameserver vs RBL mirroring

[Julian Field]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1



Alex Neuman van der Hans wrote:
> Michael Masse wrote:
>> Can someone explain the pro's and con's of each with respect to
>> performance and accuracy, or am I confused and they are not actually
>> mutually exclusive, and have nothing to do with eachother?
>>
>> Mike
>>
> Caching nameserver means "keep a copy of DNS lookups so I don't have 
> to do it again for some time". RBL Mirroring means "don't ask a remote 
> RBL every time I get a message; download the changes to the list 
> periodically".
As a general rule, you don't need your own mirror of an RBL unless you 
are doing well over 100,000 messages per day. Below that figure, most of 
the RBL managers won't give you a feed for a mirror anyway. Get a 
caching nameserver going first (essential) and see how you get on and 
measure your message throughput. If you are well into 6 or 7 figures, 
then think about asking the RBL managers for a direct feed. "rbldns" is 
the best thing to use for big RBLs, not BIND. Run rbldnsd on a different 
port and just tell BIND to feed requests for the domain to the port used 
by rbldnsd.

I can supply config snippets if necessary. I have a mirror feed for the 
SURBLs.

Jules

- -- 
Julian Field MEng CITP
www.MailScanner.info
Buy the MailScanner book at www.MailScanner.info/store

MailScanner customisation, or any advanced system administration help?
Contact me at Jules at Jules.FM

PGP footprint: EE81 D763 3DB0 0BFD E1DC 7222 11F6 5947 1415 B654
For all your IT requirements visit www.transtec.co.uk



-----BEGIN PGP SIGNATURE-----
Version: PGP Desktop 9.5.3 (Build 5003)
Comment: Fetch my public key foot-print from www.mailscanner.info
Charset: ISO-8859-1

wj8DBQFFwSCYEfZZRxQVtlQRAkBbAKC8KgFkdczsi2vrhkZMjI4q6/ze8ACfVFzb
Psu9Ib3zogMHLRLnJunQ0xs=
=QgLD
-----END PGP SIGNATURE-----

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
For all your IT requirements visit www.transtec.co.uk