<div class="gmail_quote">On Thu, Jun 18, 2009 at 12:57 PM, James Booth <span dir="ltr"><<a href="mailto:james@booths.net.nz">james@booths.net.nz</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div link="blue" vlink="purple" lang="EN-NZ">
<div>
<p><span style="font-size: 10pt; color: blue;">Thanks Steve. RAID1 with LVM will give me what I need, I was just
hoping for RAID 1+0 so I could also get the performance gain, which may be
handy if I end up with three frontends all watching and recording HD at the
same time. If I had three RAID1 arrays as per Tim’s email, and then put
RAID0 over the top, could I subsequently add in another RAID1 pair as per Tim’s
directions, and then grow the RAID0 across the extra RAID1 pair without having
to backup? I guess in short I’m asking can you currently add disks/partitions
to a RAID0 automatically without loss of data? I find many conflicting answers
on the net.</span></p></div></div></blockquote>I wouldn't worry too much about the performance - hard drives are at least an order of magnitude faster than HD streams. I believe TV3 runs around 11Mbps, a modern drive will easily handle in excess of 400Mbps. A two disk RAID1 should be capable of nearly twice the single disk read speed - when you've got multiple reads going (as its the case with streaming three files to different frontends) RAID1 should be approximately the same speed as RAID0 for the same number of drives.<br>
<br>As far as I know you can't extend RAID0 arrays with mdadm either (at least the man page says 1/4/5/6 only). My advice is that if you're really expecting to extend the array any time soon just buy the drive now.<br>
<br>By the way, that stuff you keep referring to from Tim's email was also written by me :-)<br><br>Cheers,<br>Steve<br></div>