<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
</head>
<body text="#000000" bgcolor="#FFFFFF">
On the mgs/mgt do something like:<br>
lctl --device <fsname>-OST0019-osc-MDT0000 deactivate<br>
<br>
No further files will be assigned to that OST. Reverse with
"activate". Or reboot the mgs/mdt as this is not persistent. "lctl
dl" will tell you exactly what that device name should be for you.<br>
<br>
bob<br>
<br>
<div class="moz-cite-prefix">On 7/12/2017 6:04 PM, Alexander I
Kulyavtsev wrote:<br>
</div>
<blockquote type="cite"
cite="mid:AC6DDB5E-EA98-4D5B-8C44-C35375640793@fnal.gov">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<div class="">You may find advise from Andreas on this list (also
attached below). I did not try setting fail_loc myself.</div>
<div class=""><br class="">
</div>
<div class="">In 2.9 there is setting <span style="color:
rgb(112, 112, 112); font-family: monospace; font-size: 14px;
background-color: rgb(255, 255, 255);" class="">osp.*.max_create_count=0</span><font
class="" face="Arial, sans-serif" color="#707070"><span
style="font-size: 14px; background-color: rgb(255, 255,
255);" class=""> </span></font>described at LUDOC-305.</div>
<div class=""><br class="">
</div>
<div class="">We used to set OST degraded as described in lustre
manual. </div>
<div class="">It works most of the time but at some point I saw
lustre errors in logs for some ops. Sorry, I do not recall
details.</div>
<div class=""><br class="">
</div>
<div class="">I still not sure either of these approaches will
work for you: setting OST degraded or fail_loc will makes some
osts selected instead of others.</div>
<div class="">You may want to verify if these settings will
trigger clean error on user side (instead of blocking) when all
OSTs are degraded.</div>
<div class=""><br class="">
</div>
<div class="">The other and also simpler approach would be to
enable lustre quota and set quota below used space for all users
(or groups).</div>
<div class=""><br class="">
</div>
<div class="">Alex.</div>
<div class=""><br class="">
<blockquote type="cite" class="">
<div style="margin: 0px;" class=""><span style="font-family:
-webkit-system-font, 'Helvetica Neue', Helvetica,
sans-serif;" class=""><b class="">From: </b></span><span
style="font-family: -webkit-system-font, 'Helvetica Neue',
Helvetica, sans-serif;" class="">"Dilger, Andreas" <<a
href="mailto:andreas.dilger@intel.com" class=""
moz-do-not-send="true">andreas.dilger@intel.com</a>><br
class="">
</span></div>
<div style="margin: 0px;" class=""><span style="font-family:
-webkit-system-font, 'Helvetica Neue', Helvetica,
sans-serif;" class=""><b class="">Subject: </b></span><span
style="font-family: -webkit-system-font, 'Helvetica Neue',
Helvetica, sans-serif;" class=""><b class="">Re:
[lustre-discuss] lustre 2.5.3 ost not draining</b><br
class="">
</span></div>
<div style="margin: 0px;" class=""><span style="font-family:
-webkit-system-font, 'Helvetica Neue', Helvetica,
sans-serif;" class=""><b class="">Date: </b></span><span
style="font-family: -webkit-system-font, 'Helvetica Neue',
Helvetica, sans-serif;" class="">July 28, 2015 at 11:51:38
PM CDT</span></div>
<div style="margin: 0px;" class=""><span style="font-family:
-webkit-system-font, 'Helvetica Neue', Helvetica,
sans-serif;" class=""><b class="">Cc: </b></span><span
style="font-family: -webkit-system-font, 'Helvetica Neue',
Helvetica, sans-serif;" class="">"<a
href="mailto:lustre-discuss@lists.lustre.org" class=""
moz-do-not-send="true">lustre-discuss@lists.lustre.org</a>"
<<a href="mailto:lustre-discuss@lists.lustre.org"
class="" moz-do-not-send="true">lustre-discuss@lists.lustre.org</a>><br
class="">
</span></div>
<br class="">
<div class=""><span class="" style="float: none; display:
inline !important;">Setting it degraded means the MDS will
avoid allocations on that OST</span><br class="">
<span class="" style="float: none; display: inline
!important;">unless there aren't enough OSTs to meet the
request (e.g. stripe_count =</span><br class="">
<span class="" style="float: none; display: inline
!important;">-1), so it should work.</span><br class="">
<br class="">
<span class="" style="float: none; display: inline
!important;">That is actually a very interesting
workaround for this problem, and it</span><br class="">
<span class="" style="float: none; display: inline
!important;">will work for older versions of Lustre as
well. It doesn't disable the</span><br class="">
<span class="" style="float: none; display: inline
!important;">OST completely, which is fine if you are
doing space balancing (and may</span><br class="">
<span class="" style="float: none; display: inline
!important;">even be desirable to allow apps that need
more bandwidth for a widely</span><br class="">
<span class="" style="float: none; display: inline
!important;">striped file), but it isn't good if you are
trying to empty the OST</span><br class="">
<span class="" style="float: none; display: inline
!important;">completely to remove it.</span><br class="">
<br class="">
<span class="" style="float: none; display: inline
!important;">It looks like another approach would be to
mark the OST as having no free</span><br class="">
<span class="" style="float: none; display: inline
!important;">space using OBD_FAIL_OST_ENOINO (0x229) fault
injection on that OST:</span><br class="">
<br class="">
<span class="" style="float: none; display: inline
!important;"> lctl set_param fail_loc=0x229
fail_val=<ost_index></span><br class="">
<br class="">
<span class="" style="float: none; display: inline
!important;">This would cause the OST to return 0 free
inodes from OST_STATFS for the</span><br class="">
<span class="" style="float: none; display: inline
!important;">specified OST index, and the MDT would skip
this OST completely. To</span><br class="">
<span class="" style="float: none; display: inline
!important;">disable all of the OSTs on an OSS use
<ost_index> = -1. It isn't possible</span><br
class="">
<span class="" style="float: none; display: inline
!important;">to selectively disable a subset of OSTs using
this method. The</span><br class="">
<span class="" style="float: none; display: inline
!important;">OBD_FAIL_OST_ENOINO fail_loc has been
available since Lustre 2.2, which</span><br class="">
<span class="" style="float: none; display: inline
!important;">covers all of the 2.4+ versions that are
affected by this issue.</span><br class="">
<br class="">
<span class="" style="float: none; display: inline
!important;">If this mechanism works for you (it should,
as this fail_loc is used</span><br class="">
<span class="" style="float: none; display: inline
!important;">during regular testing) I'd be obliged if
someone could file an LUDOC bug</span><br class="">
<span class="" style="float: none; display: inline
!important;">so the manual can be updated.</span><br
class="">
<br class="">
<span class="" style="float: none; display: inline
!important;">Cheers, Andreas</span></div>
</blockquote>
<br class="">
</div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Jul 12, 2017, at 4:20 PM, Riccardo Veraldi
<<a href="mailto:Riccardo.Veraldi@cnaf.infn.it" class=""
moz-do-not-send="true">Riccardo.Veraldi@cnaf.infn.it</a>>
wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div class="">Hello,<br class="">
<br class="">
on one of my lustre FS I need to find a solution so that
users can still<br class="">
access data on the FS but cannot write new files on it.<br
class="">
I have hundreds of clients accessing the FS so remounting
it ro is not<br class="">
really easily feasible.<br class="">
Is there an option on the OSS side to allow OSTs to be
accessed just to<br class="">
read data and not to store new data ?<br class="">
tunefs.lustre could do that ?<br class="">
thank you<br class="">
<br class="">
Rick<br class="">
<br class="">
_______________________________________________<br
class="">
lustre-discuss mailing list<br class="">
<a href="mailto:lustre-discuss@lists.lustre.org" class=""
moz-do-not-send="true">lustre-discuss@lists.lustre.org</a><br
class="">
<a class="moz-txt-link-freetext" href="http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org">http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org</a><br
class="">
</div>
</div>
</blockquote>
</div>
<br class="">
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
lustre-discuss mailing list
<a class="moz-txt-link-abbreviated" href="mailto:lustre-discuss@lists.lustre.org">lustre-discuss@lists.lustre.org</a>
<a class="moz-txt-link-freetext" href="http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org">http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org</a>
</pre>
</blockquote>
<br>
</body>
</html>