[fedfs-utils] [PATCH] FedFS - simple setup howto

[Chuck Lever]

On Aug 29, 2012, at 10:50 PM, Ian Kent wrote:

> On Wed, 2012-08-29 at 13:53 -0700, Chuck Lever wrote:
>> On Aug 28, 2012, at 8:45 PM, Ian Kent wrote:
>> 
>>> The thing that is still missing I think is usage of sub domains (either
>>> delegated or included within an existing DNS configuration). But I don't
>>> think we have a discovery protocol yet anyway.
>> 
>> If I understand correctly, I don't think FedFS has "subdomains." 
>> Junctions can appear anywhere in the domain's namespace, in any
>> export.  They can even refer to other domains.  But as far as I know
>> there isn't the concept of a hierarchy of domains.  The top level
>> directory of /nfs4 is a flat namespace.
> 
> I'm thinking of just the top level.
> 
> There's nothing stopping someone setting up multiple name spaces.
> 
> For example, assume you have a domain company.com and you've divided
> your DNS up like:
> 
> company.com
> sales.company.com
> engineering.company.com
> 
> AFAICS each of these can have a name space accessed via:
> 
> /nfs4/company.com
> /nfs4/sales.company.com
> /nfs4/engineering.company.com
> 
> and these sub-domains could be actually delegated in the top level
> domain or just prefixed names within the company.com DNS.

Yes, you can do that.  But perhaps a more natural way to do this with FedFS is to have the company.com FedFS domain root globally advertised (via SRV) and then put referrals in that domain's root to NFS servers that are administrated by the individual departments.  So you have:

  /nfs4/company.com
  /nfs4/company.com/sales -> NFS servers in the sales department
  /nfs4/company.com/engineering -> NFS servers in the server department

Each department can have its own NSDB, or they can share one NSDB that has multiple NCIs, or there can be a single FedFS administrator and one NSDB with one NCI for the whole domain.

> I admit it isn't great to have the root domain and sub-domains at the
> same level but I think this can be done and people with larger name
> spaces will likely do it.
> 
> Maybe there's an opportunity to think a bit about this before people
> start asking for a hierarchic name spaces, although it is out of scope
> for this task.


Agree on both counts.  This is definitely "user's guide" material, and the place we will have to draw our administrative use cases from is most likely going to be existing automounter deployments.

--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com