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DNS settings at the registrar for proper failover

I have setup my DNS entries at the registrar the following way. What I would like to achieve is to have a proper failover not just for the web, e-mail delivery & receipts (SMTP), but also for the pop3 clients. Could you please help me which one setting is preffered or any other suggestions:

A (Host)
Host      Points To        TTL
@      69.180.6.6        1 Hour
@      24.126.181.62      1 Hour
mail      69.180.6.6        1 Hour
mail2      24.126.181.62      1 Hour

CNAMES (Aliases)
Host            Points To        TTL
ftp            @            1 Hour
webmail            @             1 Hour
www            @            1 Hour
www.webmail      @            1 Hour

MX (Mail Exchange)
Priority      Host      Goes To            TTL
0      @      mail.sssconsulting.net      1 Hour
10      @      mail2.sssconsulting.net      1 Hour

==========================================================
OR
==========================================================

A (Host)
Host      Points To        TTL
@      69.180.6.6        1 Hour
@      24.126.181.62      1 Hour
mail      69.180.6.6        1 Hour
mail      24.126.181.62      1 Hour

CNAMES (Aliases)
Host            Points To        TTL
ftp            @            1 Hour
webmail            @             1 Hour
www            @            1 Hour
www.webmail      @            1 Hour

MX (Mail Exchange)
Priority      Host      Goes To            TTL
0      @      mail.sssconsulting.net      1 Hour

Any help will be greatly appreciated.
Thank you,

simprix

You could use DNS round robin like this. http://content.websitegear.com/article/load_balance_dns.htm. This is not true fail over. You would need a load balancer or a DNS service like DynDNS.

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Ted Bouskill

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Salman121

ASKER

I tested with one MX record and two IP addresses in A record as below:

MX (Mail Exchange)
Priority Host Goes To TTL
0 @ mail.sssconsulting.net 1 Hour

mail 69.180.6.6 1 Hour
mail 24.126.181.62 1 Hour

when i pinged the "mail.sssconsulting.net", it showed the first IP address, "69.180.6.6". I brough that server down and then pinged it again. This time it responded witht he second IP address, "24.126.181.62". I tested with sending mail messages as well and it seems to work OK. I just wasn't sure if this is the proper way to to setup the failover for mail server. Any comments?

Ted Bouskill

No that isn't proper fail-over. It is DNS round robin. Use two different client systems and execute a ipconfig /flushdns between pings while the first server is down. Every second request will get the first server which will fail.

Round robin DNS is NOT fault tolerant. If a server goes down, clients will get errors.

northcide

www.barracuda.com - inexpensive load balancers.

Ted Bouskill

Once again network load balancing in Windows is free and very easy to manage.

Computer101

Forced accept.

Computer101
EE Admin