samba cluster and nmbd

[Evgeny Privarotskiy]

Hi Michael,

Thanks for prompt reply.

1. Suppose that there is a need to support broadcast. In this case
nmbd should run only on one of the nodes (as you said). I am checking
the following solution. Nmbd has access to the list of Public IP's and
answers to name query requests using round robin among IP's. My
question is if this solution will be interesting to samba?

2. Regarding WINS. Do you mean manually register Public IP's in WINS
server? If I understand samba code correct, currently nmbd cannot
register several Public IP into WINS. Am I right?

Thanks in advance,
 Evgeny

On Tue, Jul 14, 2009 at 11:39 PM, Michael Adam<obnox at samba.org> wrote:
> Hi Evgeny,
>
> Evgeny Privarotskiy wrote:
>> Hi,
>>
>> I am trying to find any information about nmbd in cluster environment.
>> Ctdb project made it possible to run samba cluster. Ctdb's wiki
>> recommends to configure DNS and WINS with cluster public IP's.
>> However, it is not clear how does nmbd work in the cluster?
>> Does it run on single node or there is some synchronization between
>> different instances?
>> Please share information if you have it.
>
> The NetBIOS browsing stuff works with broadcasts. Since the nodes
> in a samba-ctdb cluster should appear as _one_ cifs server with a
> common netbios name and so on, when you start nmbd on mutliple
> nodes, then the nmbd will compete with each other about who the
> names belong to. Also the wins functionality of nmbd is not
> replicated properly in the cluster (it is not a tdb database that
> could be replicated by ctdb).
>
> So my advice is this: do _not_ start nmbd on the cluster nodes!
> (But if for some reason you really really want to start it,
> start it on one node at most, but this won't work very well
> either, since it will only register the current node's IP
> addresses.)
>
> The advice above for configuring the WINS server is referring
> to an external WINS server: Just register all the public
> IP addresses for the cluster's netbios name, just as you
> create A records for each public IP in DNS.
>
> Hope this helps.
>
> Cheers - Michael
>