Can we load balance traf[f]ic for CNAME records?

Feng He fenghe at nsbeta.info
Fri Dec 14 09:24:17 UTC 2012


于 2012-12-14 17:14, Manish Rane 写道:
> I understand that Mail Delivery load balance can be achieved by usingMX
> priorities. My concern is not that, rather I am more worries about users
> who will be using A record to configure their mail clients like IMAP or
> POP. I am thinking on load balancing their since I want users to access
> the both the ISPs to connect. I can have A/CNAME? record configured in
> my zone with *lower TTL value say 180* so that if any of the link goes
> down I can edit the zone and have the faulty entry removed which
> eventually would cost me less downtime. That way I dont need to do any
> configuration at client end since the A/CNAME record is gonna be the same.
>
> That is why I was wondering if A or CNAME can be configured for two
> different IP addresses which also holds MX Records and thus configure
> the load balancing by that way?

There are two ways of setup that.
the first, for example, imap.example.com has two A records,

imap.example.com. 900  IN  A  11.22.33.44
imap.example.com. 900  IN  A  55.66.77.88

If one server go down, half of the users have the chance to use the 
another one.

the second, imap.example.com has only one A record,

imap.example.com 900 IN A  11.22.33.44

when this server go down, you change the record value to another IP by 
hand. that's no problem for the clients ,but you must do it by hand. Or 
write a script to do this automatically for you.

Regards.



More information about the bind-users mailing list