storage server & scalability
At this moment we are preparing to build a cluster for the webservices
we offer. The main purpose of this cluster would be high availability
and high scalability. Our setup is almost ready, but we are looking at
the possibilities of the storage server we want to use.
Because of variuos reasons we would like to use a custom-built storage
server. This storage server would need to be accessed by nfs. We need
advice with 2 issues.
It seems obvious that SCSI is the way to go. However, because of the
simple fact that (S)ATA provides much more capacity (and is far less
expensive) we would like to know what you think of using SATA drives
in a storage server. And what RAID level would be a good choice? It
may be good to know that we will setup 2 identical storage servers,
one as a hot-spare, which syncs it's disks with DRBD from the main
storage server. Off-course we will be using heartbeat to take over the
ip on the hot-spare once the main storage becomes unavailable.
Another question which remains unanswered for us is how one would
scale storage. For example, if we setup a storage server with RAID 5
or RAID 6, how can we extend the RAID array with more capacity,
without losing data? Would it be as simple as plugging in another disk
at the array?
Thank you in advance for your time and answer.
Qweb Internet Services