Multiple Master servers for NIS domain

[Samuel Scott]

Does HP support multiple master NIS servers for a single domain?

[Steven Schweda]

Does anyone?

[TTr]

Not multiple masters. You can have many slave servers and have some redundancy there for your NIS clients. What exactly are you looking to do?

[Samuel Scott]

Linux supports it.

[Samuel Scott]

Guys,

Thanks for the responses.

The customer I'm supporting thinks the Master / Slave concept is not truly fault tolerant. He has 3 masters, 2 slave servers running in Linux, and finds it hard to believe HP doesn't support this.

I've explained how if necessary he can promote a slave to a master, but to my knowledge HP has no official document on setting up multiple masters (which is what he is looking for).

[Steven Schweda]

I haven't been a serious NIS user for many
years, and then mostly on Sun systems, and I
don't get out much, but it's not immediately
clear to me how you can have more than one
master NIS server (or master _anything_).
What happens if two masters disagree about
something?

I probably know even less than I thought that
I did, which wasn't much, but I was under the
impression (delusion?) that slave servers
were _the_ mechanism for supplying NIS server
redundancy.

> [...] finds it hard to believe HP doesn't
> support this.

And I don't understand how anyone could, but
that could be just more evidence of my
ignorance. If you find a good manual
explaining why this really does make sense,
please post a link.

[TTr]

> Linux supports it.

I would like to see how it is done.

Now, there is nothing that makes any server an NIS master, until there are slave servers and clients that use its maps. I don't see why you can't have multiple master servers for the same domain name but each master would be a master of its own NIS domain. But then the source files of the NIS maps would have to be in sync across the master servers. I would never set up anything like this, it is just a thought.

A single NIS master (dedicated only to create the NIS maps and propagate them to the slaves) and several NIS slave servers is very fault tolerant as long as all NIS clients bind to the slave servers only. If the master went down, the slaves continue to serve the maps and the master can be rebuilt on the same or any other server at you leisure. The only impact is that you can not add any new records to the maps while the master is down.

[Vishu]

Hi,

I agree to Steven about this. I have never come across a scenario where i saw multiple master servers. Like Master is one and it has multiple slave servers as his replicas.
When master goes down, the first available slave server started functioning as master depend upon the configuration and gives control back to Master server, when it comes up.

Please post the link which has the procedure to configure mulitple masters, even in Linux.

If it is what you said, then really thanks for a new thing to me. :-)

[VK2COT]

Hello,

This person is wrong.

Even on Linux, NIS (or as we used to call it
Yellow Pages) has the following rule:

QUOTE
Within a network there must be at least one
machine acting as a NIS server. You can have
multiple NIS servers, each serving different
NIS "domains" - or you can have cooperating
NIS servers, where one is the master NIS
server, and all the other are so-called
slave NIS servers...
END QUOTE

I used to manage many NIS and NIS+
environments. There never was
a NIS domain with multiple NIS masters.

For more details, refer to:

http://www.faqs.org/docs/Linux-HOWTO/NIS-HOWTO.html

So, NIS setup on HP-UX, or Linuyx, or Solaris
is the same...

Cheers,

VK2COT

[Samuel Scott]

Thanks for the responses. I will close this one out.

.

[TTr]

While closing this out it would help if:
1. Give some details about your earlier statement about your customer having 3 master servers.
2. Assign some points to the responses.