Anti-spam gateway recommendations, please

[glenndm]

Hello,

Although I run a tiny email server, a anti-spam gateway is vital.

Since more than 10 years, I rely on chaining an online anti-spam gateway service (www.duocircle.com) to a on-premise spam filter (popfile.sourceforge.net - magnificient but sadly orphanware) to finally Zimbra NE.
The ratio real to spam messages is normally around 1 to 100.

I'm now looking for a alternative to the duocircle online anti-spam gateway .
While it performs brilliantly during "spam" attacks (when the incoming daily message-load can increase over 100-fold ), it is rather clunky with wrongly classified messages and a very poor resolution method.
It does not help that duocircle does not really handle the local languages (dutch/french)
Which leads to frustration with users and correspondents, who then annoy me

Which online antispam filter (antivirus) do you use or recommend?
Aside from great spamblocking, an basic but user-friendly interface accessible to regular users (not only admins)for learning/resolution is key.

best regards
glenn

[Klug]

Opensource or closed?
Also free or money involved?

I used to use MailCleaner but the community version is not maintained any more (for months).

I'm testing Promox Mail Gateway on my own domain for a couple of months.
It's "just" SpamAssassin with some nice features around (full webUI, quarantine management, cluster management, etc).
So it'll work as well as you spent time tuning SA (adding generic rules, adding anti-phishing with downloaded signatures, adding URIBL, adding country-related rules, etc).
We had quite a lot of emails quarantined at first (because the french-related rules were a bit too violent) but it's working quite well in the end, the WebUI is very nice (both for admins and end-users).
That's on premise.

We're selling Vade to customers who wants a cloud security solution (not just antispam).
Works very well (anti-phishing of all kinds, filtering proxy for links, support is knowledgeable and speaks french).
I know no customers (or friends) using Vade who wants to get away from it.
But quite expensive.

A reseller started to test MailInBlack (now that the Turing test can be disable, I do not blacklist the solution any more).
Works well too (I'm waiting to see some spear-phishing tries to see how it reacts against Vade), can be hosted on premise, cheaper than Vade.
Same comment than Vade: people are happy with it.

A friend (running on O365 but still a friend) has Barracuda plugged into his tenant and is very unhappy with the solution.
Users are not able to whitelist/blacklist senders, it has to be done by the admin.
They got hit by a phishing campaign, my tuned SpamAssassin (in PMG) quarantined the emails right away on a single fact: the sending domain was less than 4 weeks old (this seems not to be tested by Barracuda).

[phoenix]

Hello,

Although I run a tiny email server, a anti-spam gateway is vital.

Why don't you try Rspamd in Zimbra?

I've just had a continuous 'attack' of two thousand 'spam' emails which were all rejected by Rspamd and the server didn't even break into a sweat.

[glenndm]

thank you for the replies
I will take a look at your suggestions.

@klug:
duocircle is a closed paying solution, so I'm open for any combination
Opensource is great (I use opensource Zimbra for many years), but orphan/abondonware is a worry.

@phoenix:
My reason for an online service is that that would deal with the hammering during a spam attack instead of my own internet connection?
the 2 attacks this year lasted each 7 days with ± 6000 message daily
I'll check rspamd too

best regards
glenn