BIND primary + secondary, how and how many

[Kevin Darcy]

I=F1aki Mart=EDnez wrote:

> HI!!!
>
>  Well the subject is a bit confused....... sorry.....
>
>  I have 4 servers (each in a diferent location and network), each of
> them have a domain with Web (apache), ftp, mail (sendmail) and bind.
>
>  NOW *each* server has configured Bind with its own domain as primary
> and the rest of domains (of the other three servers) as slaves.
>
>  Then each server is primary of the domain it owns and is secondary of
> the rest os the domains.
>
>  More graphically (NOW):
>
>  Server     primary    slaves
>  ---------  ---------  -------------------------
>  Server1    domain1    domain2, domain3, domain4
>  Server2    domain2    domain1, domain3, domain4
>  Server3    domain3    domain1, domain2, domain4
>  Server4    domain4    domain1, domain2, domain3
>
>  Well, my question is:
>
>  Is this an optimal configuration???
>
>  Or it is better to configure ONE server to be primary of ALL domains
> and the rest of the servers to configure them as secondary domain
> servers.
>
>  Server     primary    slaves
>  ---------  ---------  -------------------------
>  Server1    domain1
>  Server2               domain1, domain2, domain3, domain4
>  Server3               domain1, domain2, domain3, domain4
>  Server4               domain1, domain2, domain3, domain4
>
>  Another question is:
>
>  What about if a primary server (any server first case and server1
> second one) is down???
>
>  How do the secondaries respond or are been accessed????
>
>  Thanks in advance for any help??????

Other nameservers don't really care which of your nameserver is master
for a zone, and which are slaves:
they will fail over to a working, faster authoritative nameserver,
regardless of whether it is master or slave.

So, from a performance/server-reliability you may as well go with
whatever is easier to maintain. This would normally entail making one
server the master for all of the domains.

However, you should also assess the impact of not being able to make
changes to one or more domains while the master is down. Can you really
tolerate not being able to change *any* of your 4 domains while the
master which hosts all of 4 of them is down? Perhaps it would be better
to soften the impact by spreading the master duties around. On the other
hand, if you're setting up an automatic or semi-automatic "in case of
disaster, reconfigure slave as temporary master" mechanism, it might be
easier to do this for only one master and one of the slaves...


- Kevin