@peterbo
In response to
@trialotto and what, in your eyes, is the widely advertised
Warden Anti-spam and Virus Protection then? It is just a nice wrapper around SpamAssassin Open Source, just like many other plugins (also Kolab). I'm not using MagicSpam, but this eliminates the point.
I have to admit that I have to make clear that my previous post contains an implicit nuance, being that
"
everything commercial based on open source is fine, but commercial fees should be in line with added value : if added value is not sufficient, any commercial fee is not really justified and/or cannot be really justified - it would be "cost ineffective" for any user to pay for services that can be equally obtained by implementing underlying open source."
In essence, Warden Anti-spam and Virus is something similar : I would not recommend to pay any commercial fee for it, for reasons that should be clear by now.
As a nice example of an anti-spam and anti-virus tooling set that is based on open source, but really does add value in a commercial subscription : Spam Experts.
The reason for the latter statement is that you do not only get a highly "trained" spam machine cluster, but also the infrastructure (and worry-free usage of the solution).
One could consider to re-create a solution similar to Spam Experts, by simply installing the open source underlying Spam Experts, but one would end up with huge costs for a solution that is not as smart or well-configured as Spam Experts nowadays is.
However, to be crystal clear about the "Spam Experts as a viable and justifiable solution" statement, I must admit that it is not the best idea to purchase or pay the commercial fee that Plesk ask for their (excellent) Spam Experts extension - there are two simple reasons for the before : (on the one hand) there are providers out there that have a more cheap offer for an identical Spam Experts solution and,
more important, (on the other hand) there are (rare, but
existing) situations in which the Spam Experts extension by Plesk will not work as expected, for instance when using external nameservers in combination with a non-proper configuration of the Plesk server and the external nameserver.
In summary, I would really
recommend to consider Spam Experts for anything related to anti-spam or anti-virus objectives *.
Hope the above helps a bit and answers your question to some extent.
Kind regards........
* Note that you should always combine solutions when trying to meet anti-virus objectives - for instance, Spam Experts should be combined with Plesk Premium anti-virus. It is not only good practice, but also a "
must have" if you decide to have one control mechanism against spam or viruses on external servers : anything that mistakenly will pass rules of the control mechanism on external servers will still be checked on the local server - better be safe than sorry!