MailScanner on a cluster

[Richard Frovarp]

Dave,

You could use something like IPVS if you run Linux. Have the machine 
listen to an IP and port and have it do RR or some other method for 
distributing the load. It does support persistent connections, which is 
probably of no use in this case.

 http://www.linuxvirtualserver.org/software/ipvs.html

It does require some work to setup, but is a lot cheaper than a fancy 
Cisco system.  We use it to balance LDAP, outgoing SMTP, and webmail.

Richard

Dave Strydom wrote:

> Julian,
>
> I'm already using the DNS round-robin system of both solution 1 and
> solution 2, there is just one problem...
>
> These mailscanners are part of a webhosting setup and handle mail for
> about 2500+ different domains, I don't want to have to go update all
> MX records everytime i want to add an additional server. Also some
> people handle their own DNS records, so then it's a mission to send
> out notifications and asking people to sort out their MX records.
>
> What I am looking at doing is keeping my current "external ip's" and
> then having them nat into a cluster, but i want to know if I can run
> mailscanner on something like an openmosix cluster, this way I can
> just add servers to the cluster and not have to worry about additional
> ip's and the updates that go with it.
>
> Dave
> On 5/22/06, Julian Field <MailScanner at ecs.soton.ac.uk> wrote:
>
>> Dave Strydom wrote:
>> > Please excuse my ignorance, but can anyone point me in the right
>> > direction of:
>> >
>> > a) is it possible to run MailScanner on a cluster
>> Yes.
>> > b) If so, can you please point me to some documentation so i can read
>> > up on it please.
>> It's very easy.
>> At the simplest level, which actually works remarkably well considering
>> how cheap the solution is, is this:
>>
>> Solution 1
>> ===========
>> Create a new DNS record called mx.yourdomain.com and assign multiple
>> 'A'records to it, one for each of the IP addresses used by your cluster
>> of servers.
>> Put a single 'MX' record in your domain's DNS records, pointing to
>> "mx.yourdomain.com." (Don't forget the "." on the end).
>>
>> @        10 IN MX        mx.mydomain.com.
>> mx       IN A          192.168.99.101
>>             IN A          192.168.99.102
>>             IN A          192.168.99.103
>>             IN A          192.168.99.104
>>             IN A          192.168.99.105
>>
>> It's as simple as that. The DNS lookups will rotate through the members
>> of your cluster, spreading the messages (by quantity, not by size)
>> across your cluster.
>>
>> Solution 2
>> ===========
>> You can also do this by having multiple MX records all with the same
>> priority number, each pointing to mx1, mx2, mx3, mx4 etc.
>>
>> @        10 IN MX        mx1.mydomain.com.
>>            10 IN MX        mx2.mydomain.com.
>>            10 IN MX        mx3.mydomain.com.
>>            10 IN MX        mx4.mydomain.com.
>>            10 IN MX        mx5.mydomain.com.
>> mx1       IN A          192.168.99.101
>> mx2       IN A          192.168.99.102
>> mx3       IN A          192.168.99.103
>> mx4       IN A          192.168.99.104
>> mx5       IN A          192.168.99.105
>>
>> Some people argue that this is better as it is more likely to deliver
>> mail quicker when you take some of your servers out of action. They are
>> possibly right.
>>
>> Solution 3
>> ===========
>> You can also do this by spending a fortune on Cisco load balancers and
>> have heartbeat monitoring systems, etc. But it won't make any big
>> difference, but you will have a very expensive Cisco box to look after
>> and a big hole in your bank balance.
>>
>> Again, can someone please put this in the Wiki for me?
>>
>> -- 
>> Julian Field
>> www.MailScanner.info
>> Buy the MailScanner book at www.MailScanner.info/store
>> Professional Support Services at www.MailScanner.biz
>> MailScanner thanks transtec Computers for their support
>>
>> PGP footprint: EE81 D763 3DB0 0BFD E1DC 7222 11F6 5947 1415 B654
>>
>>
>> -- 
>> This message has been scanned for viruses and
>> dangerous content by MailScanner, and is
>> believed to be clean.
>> MailScanner thanks transtec Computers for their support.
>>
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>>
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>>
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>>
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>
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>


-- 
Richard Frovarp
EduTech System Administrator
1-701-231-5127 or 
1-800-774-1091