<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Aug 21, 2015 at 5:47 PM, Bruce Dawson <span dir="ltr"><<a href="mailto:jbd@codemeta.com" target="_blank">jbd@codemeta.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div>On 08/21/2015 05:30 PM, Tom Buskey
wrote:<br>
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<div class="gmail_quote">On Fri, Aug 21, 2015 at 3:33 PM,
Bruce Dawson <span dir="ltr"><<a href="mailto:jbd@codemeta.com" target="_blank">jbd@codemeta.com</a>></span>
wrote:<br>
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<div bgcolor="#FFFFFF" text="#000000"> For this rainy
weekend, please consider the following:<br>
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I'm constructing a new server and want 2 KVM guest
systems on it. There are 3 4TB drives on it. At the
moment, assume one 4TB drive will be reserved for the
KVM host. The server has 16GB of RAM.<br>
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<div>I wouldn't ever run ZFS on a single disk if I cared
about the data. It's like running RAID0; get an error,
you lose your all your data. Actually, you might recover
data from a RAID0 non-ZFS.<br></div>
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Oh - but I thought ZFS will mirror "filesystems" within the pool
(probably with much poorer performance)? At any rate, I'm thinking
the first approach is the best.</div></blockquote><div> </div><div>You *can* setup the zpool to make 2 copies (copies=2) inside a single device. However, if the hardware fails, you lose data. The usual zpool setups are mirror or a raidz across multiple devices. raidz is similar to RAID5 w/o the write hole.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000"><span class=""><blockquote type="cite"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div>You can use iSCSI on ZFS to give your KVMs a a raw
block device instead of a zfs partition w/ a QCOW2
file. I've only done the zfs partition & qcow2, not
the iSCSI block. <br></div>
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I didn't know ZFS would provide that. Guess I've got more reading -
I wonder if it'll be faster.</div></blockquote><div><br></div><div>I know it is in Solaris. I've head of others doing it in BSD. I've not done it in Linux yet. Linux hasn't solidified iSCSI target/initiators like the others.</div><div> </div></div></div></div>