<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
pre
{mso-style-priority:99;
mso-style-link:"HTML Preformatted Char";
margin:0in;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New",serif;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
span.HTMLPreformattedChar
{mso-style-name:"HTML Preformatted Char";
mso-style-priority:99;
mso-style-link:"HTML Preformatted";
font-family:"Courier New",serif;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:2057927646;
mso-list-template-ids:-2050201166;}
@list l0:level1
{mso-level-number-format:bullet;
mso-level-text:\F0B7;
mso-level-tab-stop:.5in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Symbol;}
@list l0:level2
{mso-level-number-format:bullet;
mso-level-text:o;
mso-level-tab-stop:1.0in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:"Courier New",serif;
mso-bidi-font-family:"Times New Roman";}
@list l0:level3
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:1.5in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level4
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:2.0in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level5
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:2.5in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level6
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:3.0in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level7
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:3.5in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level8
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:4.0in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
@list l0:level9
{mso-level-number-format:bullet;
mso-level-text:\F0A7;
mso-level-tab-stop:4.5in;
mso-level-number-position:left;
text-indent:-.25in;
mso-ansi-font-size:10.0pt;
font-family:Wingdings;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal">Hi Ben,<o:p></o:p></p>
<p class="MsoNormal">Unfortunately, I missed your response two months ago. Somehow it didn’t get to my mailbox. Found it on the web. I would like to revisit this question.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I think I understood your explanation. Our proposal is to add an ignore_multipaths section to multipath.conf that looks like the following:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-family:"Courier New",serif">ignore_multipaths<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New",serif">{<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New",serif"> name "flashgrid*"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New",serif">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New",serif"><o:p> </o:p></span></p>
<p class="MsoNormal">This example should prevent multipathd from touching any DM devices with names starting with ‘flashgrid’<o:p></o:p></p>
<p class="MsoNormal">The justification is that this will allow custom implementations of multipath management that also use dmsetup and that can co-exist on the same system with multipathd.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is this possible to do? We will be happy to do testing.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you!<o:p></o:p></p>
<p class="MsoNormal">-Artem<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt"><o:p> </o:p></span></p>
<div class="MsoNormal" align="center" style="text-align:center"><span style="font-size:9.0pt">
<hr size="2" width="100%" noshade="" style="color:black" align="center">
</span></div>
<ul type="disc">
<li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
<em><span style="font-family:"Calibri",sans-serif">From</span></em>: "Benjamin Marzinski" <bmarzins redhat com><o:p></o:p></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
<em><span style="font-family:"Calibri",sans-serif">To</span></em>: device-mapper development <dm-devel redhat com><o:p></o:p></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
<em><span style="font-family:"Calibri",sans-serif">Subject</span></em>: Re: [dm-devel] multipathd removing DM devices that don't belong to it<o:p></o:p></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
<em><span style="font-family:"Calibri",sans-serif">Date</span></em>: Mon, 22 Jun 2015 11:04:38 -0500<o:p></o:p></li></ul>
<div class="MsoNormal" align="center" style="text-align:center"><span style="font-size:9.0pt">
<hr size="2" width="100%" noshade="" style="color:black" align="center">
</span></div>
<pre style="orphans: auto;text-align:start;widows: 1;-webkit-text-stroke-width: 0px;word-spacing:0px"><span style="color:black">On Tue, Jun 16, 2015 at 10:02:23PM +0000, Artem Danielov wrote:<o:p></o:p></span></pre>
<pre><span style="color:black">> Hello,<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> Looking for an advice on whether this is an expected behavior or a bug.<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> device-mapper-multipath-0.4.9-77.el7.x86_64<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> When multipathd service starts it will remove any DM devices with<o:p></o:p></span></pre>
<pre><span style="color:black">> multipath target, even if the underlying devices are blacklisted.<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> We are trying to use dmsetup directly to implement custom multipath<o:p></o:p></span></pre>
<pre><span style="color:black">> management logic separate from multipathd. But unfortunately if multipathd<o:p></o:p></span></pre>
<pre><span style="color:black">> is present and enabled it removes DM devices with multipath target that we<o:p></o:p></span></pre>
<pre><span style="color:black">> create.<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> Is this a bug?<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">I don't know if I'd call it a bug. It is certainly how multipath is<o:p></o:p></span></pre>
<pre><span style="color:black">designed to work. The issue is this. When you start multipathd up do a<o:p></o:p></span></pre>
<pre><span style="color:black">reconfigure. It doesn't know if the configuration has changed. So, if<o:p></o:p></span></pre>
<pre><span style="color:black">there are devices configured and it doesn't think they should be, it<o:p></o:p></span></pre>
<pre><span style="color:black">assumes that you've changed your configuration, and you'd like it to use<o:p></o:p></span></pre>
<pre><span style="color:black">your current configuration, which means removing devices that no longer<o:p></o:p></span></pre>
<pre><span style="color:black">are allowed.<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">I don't see any way of making this work, without adding a section to the<o:p></o:p></span></pre>
<pre><span style="color:black">multipath.conf file to ignore devices with certain wwids entirely (which<o:p></o:p></span></pre>
<pre><span style="color:black">is different from blacklisting them).<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">-Ben<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> Thanks for your help!<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> Artem Danielov | Chief Technology Officer | FlashGrid Inc. |<o:p></o:p></span></pre>
<pre><span style="color:black">> [1]artem flashgrid io | +1-503-568-5249<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> References<o:p></o:p></span></pre>
<pre><span style="color:black">> <o:p></o:p></span></pre>
<pre><span style="color:black">> Visible links<o:p></o:p></span></pre>
<pre><span style="color:black">> 1. <a href="mailto:artem">mailto:artem</a> flashgrid io<o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<pre><span style="color:black">> --<o:p></o:p></span></pre>
<pre><span style="color:black">> dm-devel mailing list<o:p></o:p></span></pre>
<pre><span style="color:black">> dm-devel redhat com<o:p></o:p></span></pre>
<pre><span style="color:black">> <a href="https://www.redhat.com/mailman/listinfo/dm-devel">https://www.redhat.com/mailman/listinfo/dm-devel</a><o:p></o:p></span></pre>
<pre><span style="color:black"><o:p> </o:p></span></pre>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</body>
</html>