Anti-Spam for Exchange 2003?

[Confused]

Hi all,

Have just set up an Exchange 2003 server, and some of the accounts (which were on a shared hosting account previously) get somewhere in the order of 500+ spam messages a day!

Does anyone know of an anti-spam for Exchange which could cut some of these messages down?

Thanks in advance

Confused

 

[loup garou]

How much are you willing to pay? It's hard to beat a monthly service like MessageLabs. It has the benefit of scanning and removing viruses and being a backup incoming mailserver as well. Plus, the setup is easy and there's little to no maintenance: just change a couple mx records and lock your smtp traffic down to only accept only from their IPs. I have a dozen or so clients using ML's service and it's wonderful.

 

[HeroOfPellinor]

We're converting to Exchange 2003 in a couple months. It's my understanding that you can utilize open relay blacklists. That alone should knock out 80-90% of the spam. If that fails, I plan to go with GFI MailEssentials.

 

[edmicman]

Is there a way to integrate SpamAssassin with Exchange? We're moving soon to Exchange from a linux mail server, and we currently us SA with EXCELLENT results. I'm going to miss the spam filtering, but our person leading the conversion says Exchange and Outlook 2003 have built in spam filters that should work, too. Who knows....

 

[JoeCDaMan]

Our company is going through a similar transition and are for the first time going to be administering our own 2003 exchange on a 2003 server. Right now we are looking to support 20 email boxes. Can someone reccomend other 3rd party services that will handle the spam filtering? Also is there software you can buy to do these services locally?

 

[SagaLore]

My first suggestion is to not install anti-spam on the Exchange server. Your exchange server will get bombarded with just as much spam as before, and have to handle the load of processing it all to block it.

I have found that there are several antispam appliances available that actually cost LESS than the competing software solutions. Not only do you get a dedicated machine for it, but it's typically hardened since it's a linux or sun box. Also if your exchange server had to go down for maintenance or something went wrong, then appliance would queue the emails until it came back up.

Let me know what your estimated budget is and I can recommend a few products that I have personally tested.

 

[SagaLore]

Originally posted by: HeroOfPellinor
We're converting to Exchange 2003 in a couple months. It's my understanding that you can utilize open relay blacklists. That alone should knock out 80-90% of the spam. If that fails, I plan to go with GFI MailEssentials.

That is true - I would say maybe more around 70% if you use rbl's with low false positive rates. If you go this route, use these lists: optimized spam blacklists

But everytime you get an email, regardless if it's spam or not, the exchange server has to take cpu time for every email received. I might be mistaken, but I believe Ex03 does the lookup after it receives the email, instead of like many professional antispam products that run the lookup during the initial connection from the sending server. If you have a low load server then you still have the advantage of making email more convenient for the users as well as saving hard drive space.

 

[SagaLore]

Originally posted by: edmicman
Is there a way to integrate SpamAssassin with Exchange? We're moving soon to Exchange from a linux mail server, and we currently us SA with EXCELLENT results. I'm going to miss the spam filtering, but our person leading the conversion says Exchange and Outlook 2003 have built in spam filters that should work, too. Who knows....

Run your linux server as a mail relay, route inbound smtp traffic through it and then send it to the Exchange server. Outlook 2003 spam filtering is handled user-side, not server-side.

 

[Syran]

Barracuda Spam Firewall, we use the Model 300 where I work, and it's dropped our overall numbers quite a bit.

We used to average 10k emails per day, with less then 5% being non-spam.
These days, we average 3-4k emails, and normally have ~ 500 legit emails.

In the lifetime of the unit so far, we've had 1,368,774 emails come in, while only 67,430 were allowed emails.

 

[SagaLore]

Originally posted by: Syran
Barracuda Spam Firewall, we use the Model 300 where I work, and it's dropped our overall numbers quite a bit.

We used to average 10k emails per day, with less then 5% being non-spam.
These days, we average 3-4k emails, and normally have ~ 500 legit emails.

In the lifetime of the unit so far, we've had 1,368,774 emails come in, while only 67,430 were allowed emails.

I wasn't that impressed with it when I demoed it. It's a great price, but you're buying a linux server that runs spamasassin and clam av. So basically you're paying for the hardware (which is none too impressive) and the support for opensource software.

Bayesian analysis works great for single-user and often a small group that have a related theme of business, but in a multi-theme large corporate environment, bayesian fails and causes more false positives than any good that it does.

 

[Booty]

Okay, so - our company is looking at this whole issue as well. Is the solution to run a linux-based mail server and then relay it to the Exchange server? If so, does it really matter what mail server you're running on the Linux box? And any general guidelines to what hardware to use to handle certain loads? As in, if we're getting 2k emails per day, would an older P3 700 box do?

I'd love to get some more information on this stuff... it definitely seems more economical to do it this way than to either buy an appliance or pay for a third party service - especially since the owner has already heard of Spam Assassin being a free solutions and basically said, "Find a way to make it work."

 

[Joemonkey]

We're using MailFrontier, it works really well. Has a little bit of a learning curve, but it is freaking awesome as far as customizability. It runs on a separate server than Exchange as well.