setting up round robin

[Mark Andrews]

> 
> On Jan 23, 2007, at 9:24 AM, Andy Shellam (Mailing Lists) wrote:
> 
> > jeff donovan wrote:
> >> greetings
> >>
> >> I'm not having any success setting up round robin dns for my imap
> >> servers.
> >> here is what I have done,
> >>
> >>
> > [cut]
> >> getting errors about multiple RR's, and that the option multiple
> >> cnames is obsolete
> >>
> >> okay,..
> >> so um, is there a better way to achieve this goal ?
> >>
> >
> > I had the same problem doing exactly the same thing with MX records.
> > It's not ideal, but the only way around it is to repeat the A  
> > definitions:
> >
> > imap1.bar.net.	60	IN	A	192.168.1.1
> > imap2.bar.net.	60	IN	A	192.168.1.2
> > imap3.bar.net.	60	IN	A	192.168.1.3
> > imap4.bar.net.	60	IN	A	192.168.1.4
> >
> > imap.bar.net.	60	IN	A	192.168.1.1
> > imap.bar.net.	60	IN	A	192.168.1.2
> > imap.bar.net.	60	IN	A	192.168.1.3
> > imap.bar.net.	60	IN	A	192.168.1.4
> >
> >
> > That is, if you want people to be able to go directly to  
> > "imap1.bar.net" as well as "imap.bar.net" - if not, you only need  
> > the second block.
> >
> >
> > Andy
> >
> 
> 
> Thanks for the reply.
> 
> yes i do need them to be able to access imap1 or imap2 directly.
> will give it a go.
> 
> thanks
 
 
	The long term solution is to define SRV use for IMAP.

	e.g.
		_imap._tcp.imap.bar.net SRV 0 0 143 imap1.bar.net.
		_imap._tcp.imap.bar.net SRV 0 0 143 imap2.bar.net.
		_imap._tcp.imap.bar.net SRV 0 0 143 imap3.bar.net.
		_imap._tcp.imap.bar.net SRV 0 0 143 imap4.bar.net.

		_imaps._tcp.imap.bar.net SRV 0 0 993 imap1.bar.net.
		_imaps._tcp.imap.bar.net SRV 0 0 993 imap2.bar.net.
		_imaps._tcp.imap.bar.net SRV 0 0 993 imap3.bar.net.
		_imaps._tcp.imap.bar.net SRV 0 0 993 imap4.bar.net.

	A one page RFC after the boiler plate should suffice.

	Mark
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org