Re: [9fans] Help with two small shared file servers

[Bakul Shah <bakul@bitblocks.com>]

On Wed, 17 Aug 2011 13:09:47 +0300 =?UTF-8?B?QXJhbSBIxIN2xINybmVhbnU=?= <aram.h@mgk.ro>  wrote:
> Hello,
>
> I'm looking for advice on how to build a small network of two file
> servers. I'm hoping most servers to be Plan9, clients are Windows and
> Mac OS X.
>
> I have 2 houses separated by about 40ms of network latency. I want to
> set some servers in each location and have all data accessible from
> anywhere. I'll have about 2TB of data at each location, one location
> will probably scale up.
	...
> Is 9p suitable for this? How will the 40ms latency affect 9p
> operation? (I have 100Mbit).

With a strict request/response protocol you will get no more
than 64KB once every 80ms so your throughput at best will be
6.55Mbps or about 15 times slower than using HTTP/FTP on
100Mbps link for large files.  [John, what was the link speed
for the tests in your thesis?]

> Right now (only one location) I am using a Solaris server with ZFS
> that serves SMB and iSCSI.

Using venti in place of (or over) ZFS on spinning disks would
incur further performance degradation.

> Any tips are welcomed :-),

Since you want everything accessble from both sites, how about
temporarily caching remote files locally?  There was a usenix
paper about `nache', a caching proxy for nfs4 that may be of
interest. Or may be ftpfs with a local cache if remote access
is readonly?