You configuration is fine with one recommendation: You would off load additional workload from the main server by having it send all outbound e-mail through a smart host, that being the Ant-spam server. This way, the server does not have to do outbound resolution and communications with all the other Internet servers, it simply sends all outgoing to the next server.
They way you are tiering your servers is actually a recommended way once a server reaches saturation. Example, a client I consult for is in the process of splitting the work load from one server to 2. The front server which will be configured for S&F for all domains and will do all JunkMail scanning and do all the receiving and sending to the Internet. The main server will do all Imail functions and Declude Virus Scanning. But again, all incoming and outgoing will flow through the front server, the main server sending all outbound to it to offload that work from the main server. John Tolmachoff Engineer/Consultant/Owner eServices For You > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:Declude.JunkMail- > [EMAIL PROTECTED] On Behalf Of decjunkmail > Sent: Wednesday, June 23, 2004 7:40 PM > To: [EMAIL PROTECTED] > Subject: RE: [Declude.JunkMail] AutoWhite by eServices > > Here's why we are converting our "monolithic" Imail/Declude servers to a multi-tier > store & forward configuration as follows: > > Incoming MX servers: > > Receives inbound mail from Internet > Runs Declude anti-virus to delete all viruses (single global config) > Forwards all mail to Anti-spam servers > > Anti-spam servers: > > Receives de-virused email from MX servers > Runs Declude junkmail with per-domain settings > Forwards mail to mailbox servers > > Mailbox servers: > > Runs IMAP, POP, WebMail Mailboxes > Delivers outbound mail directly for - > Locally originated email > Internet-originated but SMTP authenticated remote mail > > > The reason for this migration is a "love/hate" relationship with Ipswitch Imail: > > It's cost effective and has the features we need (plus the support for Declude plug- > ins), BUT > > It is a CPU hog - WebMail or IMAP often spike the server > It has been buggy at times (recent IMAP problems for example) > It cannot be clustered - all functions for a domain must be on one server > It does not have any HA (high-availability) or redundancy capability > > By offloading incoming MX, virus scanning, and spam blocking to other servers we are > creating a much more robust configuration. > > Massive virus attacks or spam attacks will not affect our user's ability to access their > existing email boxes via pop/imap/webmail. > > Scalability -- as virus and spam continue to grow much faster than real > mail/mailboxes, we can put extra processing power where it is needed most. > Currently, we had to prune our Declude rules/filters because they were spiking our > boxes to 100% cpu too much. > > High-availability -- (partially) By isolating the mailbox functions (pop,imap,webmail) > and keeping relatively simpler inbound handling/queuing on separate servers, we > preserve the ability to receive inbound mail even if we have crashes/bugs/failures in > mailbox processing. > > For our needs, we prefer several affordable servers distributing the tasks than one > mega-server box -- better protection against human errors/mistakes which are more > likely than hardware failures day-in and day-out. > > Finally, by modularizing the processing, we gain a little more freedom - in the future > we might choose to replace one of the processing nodes with a different > vendor/technology. Replacing one function is easier than trying to do an en masse > migration the entire mail system. > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:Declude.JunkMail- > [EMAIL PROTECTED] On Behalf Of John Tolmachoff (Lists) > Sent: Wednesday, June 23, 2004 6:01 PM > To: [EMAIL PROTECTED] > Subject: RE: Re[2]: [Declude.JunkMail] AutoWhite by eServices > > > A client has a pair of generic incoming MX servers. These then feed > > into a Declude server, storing and forwarding to the mailbox server. > > The mailbox server does its own outbound mail. > > > I'd like to know if it will ever be possible to do this, perhaps by a > > routine that can parse the log on the mail box server(in the case of > > AutoWhite) or by remote interrogation of web address lists(in the case > > of Declude's whitelist feature). I fear that not enough people are > > using Declude as a store and forward device and therefore demand will > > not be high enough to justify the change. > > The issue as you have pointed out is that both Declude and AutoWhite for > Declude need to see both incoming and outgoing to work. > > Generally speaking, it appears that most configurations where Imail/Declude > scan the incoming only for a S&F domain are in corporate configurations > where it is used as a cost effective well balanced tool to fight incoming > viruses and spam. I myself would like to understand why the company policy > or network admins feel this is the way it should be. Having Imail/Declude > process both incoming and outgoing has multiple benefits. > > You are correct in that there has not been enough interest/request for this > kind of function, and to be broad to be used enough to be able to work with > multiple e-mail servers that are handling the actual e-mail would create a > lot of overhead. If the different types of e-mail servers, such as Exchange > or Postini or Mdameon had some common form of logging that would be one > thing. > > If there is interest in say one flavor of server, say Exchange, for this > function, I am open to consider looking at ways to make it work. > > John Tolmachoff > Engineer/Consultant/Owner > eServices For You > . > > --- > [This E-mail was scanned for viruses by Declude Virus (http://www.declude.com)] > > --- > This E-mail came from the Declude.JunkMail mailing list. To > unsubscribe, just send an E-mail to [EMAIL PROTECTED], and > type "unsubscribe Declude.JunkMail". The archives can be found > at http://www.mail-archive.com. --- [This E-mail was scanned for viruses by Declude Virus (http://www.declude.com)] --- This E-mail came from the Declude.JunkMail mailing list. To unsubscribe, just send an E-mail to [EMAIL PROTECTED], and type "unsubscribe Declude.JunkMail". The archives can be found at http://www.mail-archive.com.
