Redundant Mail server

Hi,

I have a server that at the moment keeps falling over - I have another server with a different ISP with the same mail config on it. All Windows BTW, running Imail 7.

Now I want to setup the second email server to be redundant for the first so if it fallsover it just swtiches to that one.

All our clients use - pop3.domain.com and smtp.domain.com - and
MX[0] goto POP3

Now I obviously want the smtp and pop3 a records to change to a different IP address for the redundant server if the primary server goes down the MX records can then stay the same.

But how do I do this in DNS.

Pretty much want to do this with my Web and database stuff also.

Then I want to set up nameservers of my own and leave host one behind.

BTW never use - http://www.interhost.co.uk/ my server has been down all weekend and he is not answering his phone.

Thx

my understanding of this would be to simply addmultiple MX records in your dns.

The first dns record will have priority, then second then third. this works with "A" records too.

-ab
http://www.diywebserver.com


ps. I am not sure what you meant by this: "Then I want to set up nameservers of my own and leave host one behind."

Thank Bob,

Yes htis is what i suspected you can set up MX[0] MX [1] etc but do they actually take it in order? Seems so, so that answers part one I will test that.

however with A records how does it know the order? Does it just have to be further up the list or can you specify an order like with mx records.

Also yes I want to set up my own nameservers but am having real difficulties understabding the whole thing.

This will definatley help for now - but adds more hops to my servers than is required and adds failure points with a host I dont want to use.

Thx

There is a priority number associated with each MX record. The priority number controls the order in which the mail servers will be accessed.

There is NO priority number for an A record, so you can't simply tell it to hop to a different server.

Hi,

Would this work then:

User A comes in on pop3.domain.com to download there emails.

Now I have two email servers at 125.0.0.1 and 125.0.0.2

.1 is down so I need it to direct to .2 I set up the DNS as follows as far as I can see then this is how I do it. It tries the mani MX 0 and fails so looks for second highest record MX 10 so it now knows the ip adress of the mail server in question - however as I need it to go to pop3 port on server .2 will it follow the same rule - ie first pop3 record is fail find another one and try?

pop3 IN A 125.0.0.1
smtp IN A 125.0.0.1
IN MX 0 125.00.0.1
IN MX 10 125.0.0.2
pop3 IN A 125.0.0.2
smtp IN A 125.0.0.2

Thx for any assistance on this.