RE: [cobalt-users] Hypathetical redundancy system

["aljuhani" <aljuhani@xxxxxxxxx>]

Hello Ian,

I think for mail, it is best to use a backup mail server with a low priorty pointing main1 to main2.  For the DNS, there are also other things to consider like TTLs to minimize downtime between change overs.

DNS RFCs are all available here:
http://www.dns.net/dnsrd/rfc/

Regards,
aljuhani@xxxxxxxxx

======= Original Message =======

  From: Ian cobalt-users@xxxxxxxxxxxxxxx 
  To: cobalt-users@xxxxxxxxxxxxxxx 
  Sent: Sat Feb 22 16:41:01 2003
  Subject: [cobalt-users] Hypathetical redundancy system 

Hi guys,

Just wondering if this would be a possible solution as a method of ensuring
redundancy using RaQs.

Basically, if I have two identical in every respect raq4r's, say for arguments
sack one called main1 and the other main2, with main1 being the server that all
our vsites use to maintain there sites on etc, and main2 kept in sync by use of
the cmu, ris or ryssink (spelt wrong i know) on say a weelly or daily basis by
way of a cron job, and...

I then set up the dns primary name server to point all services to main1 and the
secondary name server to point all services to main2.

So long as main1 is functioning, then all requests etc would go to the main1
vsites, but if the main1 server was down, then the main2 server would get the
dns requests which would then point all services to the main2 vsites.

First of all, is this an acceptable dns usage convention and secondly, would
there be any easy way of arranging automatically that as soon as main1 came back
online, that all emails sat in the main2 vsites email accounts, got sent onto
the same email accounts on main1.

This is something I have been toying with for some time, i.e. if the primary
server that all the vsites resides on goes down for what ever reason, or has to
be taken offline for repair etc, that the secondary server would take over as if
nothing was wrong, and no one would be any the wiser.

It has got to be harder than this to be feasible, but maybe the simple things in
life can be achieved some time.

The advise, suggestions and guidance of those more knowledgable on this list
than myself is more than welcomed....

Thanks

Ian