On Sun, 13 Jun 1999 22:45:52 +0300 (GMT+0300), Yedidya Bar-david
<[EMAIL PROTECTED]> wrote:
>Hi
>
>[EMAIL PROTECTED] wrote:
>>
>> HI
>>
>> I'm looking into a way to make my disk server redundent
>> I tought of making two servers, the same, and mirror
>> their disk.
>>
>[cut stuff]
>> any ideas ?
>
>There is a project that does something like 'Symmetrical NFS', i.e.
>two (more?) machines have identical sub-trees, every write to one
>of them is written to the other.
Another approach is the one taken by the SAN crowd (SAN = Storage Area
Networks). By using Fibre Channel based arrays of multiple disks and machines
it is possible to prevent a single point of failure (disks are in RAID
configuration and there are multiple machines hooked in parallel to the same
array) .
Since the network protocol is now at the block level rather than the
filesystem level, you need a special file system that knows how to "lock"
blocks on the disk before it modifies them, so that multiple machines can
coexsist on the same fibre channel, sharing the same partition, without
corrupting the shared partition.
There is an experimental project for such a file system on Linux. I think it's
called GFS, but you can check freshmeat to be sure.
Also, if you use a Fibre Channel switch, you get great performance as a bonus.
udi
