<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Exchange Server">
<!-- converted from text --><style><!-- .EmailQuote { margin-left: 1pt; padding-left: 4pt; border-left: #800000 2px solid; } --></style>
</head>
<body>
<meta content="text/html; charset=UTF-8">
<style type="text/css" style="">
<!--
p
{margin-top:0;
margin-bottom:0}
-->
</style>
<div dir="ltr">
<div id="x_divtagdefaultwrapper" style="font-size:12pt; color:#000000; background-color:#FFFFFF; font-family:Calibri,Arial,Helvetica,sans-serif">
<p>Because of the issue highlighted by Andreas - a great number of possible states when a job is running - Cray does our upgrades with the system quiet. Live upgrades aren't something we even consider - The potential damage is too large for the time saved.
Especially since the actual *upgrade* usually doesn't take very long at all, generally speaking. For 2.4 to 2.5, the 'clean' version is just stop activity to the filesystem, unmount it on clients, stop it/unmount it server side, install the new Lustre RPMs,
and start it up again. This is relatively quick.<br>
</p>
</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> lustre-discuss <lustre-discuss-bounces@lists.lustre.org> on behalf of Dilger, Andreas <andreas.dilger@intel.com><br>
<b>Sent:</b> Sunday, July 10, 2016 5:53:38 PM<br>
<b>To:</b> Peter Bortas<br>
<b>Cc:</b> lustre-discuss@lists.lustre.org<br>
<b>Subject:</b> Re: [lustre-discuss] Is live upgrade of 2.4 to 2.5 unproblematic?</font>
<div> </div>
</div>
</div>
<font size="2"><span style="font-size:10pt;">
<div class="PlainText">We typically test 2.x->2.x+1 upgrades, both live and offline, for every version of Lustre. That said, there are a large number of possible states that may occur with a running job, so it isn't possible to test everything. If you are ready
to abort the long-running job, then trying the live upgrade and having to restart if it fails isn't any worse.
<br>
<br>
I'd always recommend to make a backup of the MDT, regardless of whether you are doing an upgrade or not, since it is a lot easier to restore only the MDT if there are problems than to restore the whole filesystem.
<br>
<br>
Cheers, Andreas<br>
<br>
> On Jul 8, 2016, at 09:08, Peter Bortas <bortas@gmail.com> wrote:<br>
> <br>
> I'm upgrading a few ZFS backed filesystems from 2.4.2 to 2.5.3 (both<br>
> from the llnl chaos branch). Clients are already running 2.5EE. It's a<br>
> simple setup with no failover or mirroring of MDSs or OSSs. Originally<br>
> the plan was to do this with the filesystems unmounted on the clients,<br>
> but it looks like it will be hard to get a window to do that any time<br>
> soon.<br>
> <br>
> Are there any known problems just doing an online upgrade 2.4 -> 2.5?<br>
> <br>
> Is the recommended method still OSSs first and MDS last?<br>
> <br>
> (Obviously the clients will lock up if they access these filesystems,<br>
> but locking them up for a fraction of a day beats aborting a 7 day<br>
> compute job.)<br>
> <br>
> Regards,<br>
> -- <br>
> Peter Bortas, NSC<br>
> _______________________________________________<br>
> lustre-discuss mailing list<br>
> lustre-discuss@lists.lustre.org<br>
> <a href="http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org">http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org</a><br>
_______________________________________________<br>
lustre-discuss mailing list<br>
lustre-discuss@lists.lustre.org<br>
<a href="http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org">http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org</a><br>
</div>
</span></font>
</body>
</html>