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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I’m thinking of using ZFS as a low level block device for drbd.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Like:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">ZFS </span><span lang="EN-US" style="font-family:Wingdings">à</span><span lang="EN-US"> drbd
</span><span lang="EN-US" style="font-family:Wingdings">à</span><span lang="EN-US"> LVM
</span><span lang="EN-US" style="font-family:Wingdings">à</span><span lang="EN-US"> iSCSI<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The reason is as follows:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- I would like to speed up reading and writing by using large read and write caches (ssd based) (ZFS ZIL and L2ARC).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Currently my storage is 100% SSD based. It would be nice if a mixed SSD/HD storage system could be build. $$$.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- I like the copy on write feature of ZFS<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- I like the ZFS snapshot feature and being able to replicate the data to a non drbd system (for backup)
<a href="http://docs.huihoo.com/opensolaris/solaris-zfs-administration-guide/html/ch06.html">
http://docs.huihoo.com/opensolaris/solaris-zfs-administration-guide/html/ch06.html</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- I have tested Flashcache in the past but this did not work reliable in a two node storage cluster setup. For some reason unknown the cached data was not replicated (correctly) to the other drbd node which of course
resulted in corrupted data.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Does anybody have some experience with this kind of setup?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Are there some cons why this setup should not be used?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Maurits van de Lande<o:p></o:p></span></p>
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