On Fri, Dec 9, 2011 at 10:27 AM, Alan McKay <alan.mckay at gmail.com> wrote: > > Now my questions : > We are not using iSCIS yet at work but I see a few places where it would be > useful e.g. a number of heavy-use NFS mounts (from my ZFS appliance) that I > believe would be slightly more efficient if I converted them to iSCSI. I > also want to introduce some virtual machines which I think would work out > best if I created iSCSI drives for them back on my Oracle/Sun ZFS appliance. This doesn't directly apply, but this nfs appliance vendor wants you to think that nfs isn't as bad as you might think: http://www.bluearc.com/bluearc-resources/downloads/analyst-reports/BlueArc-AR-NFSmyths.pdf Overcommitting for de-dup/compression might be harder with iscsi - resizing filesystems would be a lot harder. > I mentioned iSCSI to the guy whose work I have taken over here so that he > can concentrate on his real job, and when I mentioned that we should have a > separate switch so that all iSCSI traffic is on it's own switch, he balked > and said something like "it is a switched network, it should not matter". Is it a single switch? Otherwise you share the bandwidth on the trunk connections. > But that does not sit right with me - the little bit I've read about iSCSI > in the past always stresses that you should have it on its own network. > > So 2 questions : > - how important is it to have it on its own network? > - is it OK to use an unmanaged switch (as long as it is Gigabit), or are > there some features of a managed switch that are desirable/required with > iSCSI? I've seen recommendations to use jumbo frames for iscsi - and if you do that, everything on that subnet needs to be configured for them. -- Les Mikesell lesmikesell at gmail.com