<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
On 04/22/2011 03:30 PM, Laurent Bigonville wrote:
<blockquote cite="mid:20110422120009.481030c6@eldamar.bigon.be"
type="cite"><span class="moz-txt-citetags">> > </span>size=500G
features='1 queue_if_no_path' hwhandler='1 rdac' wp=rw<br>
<blockquote type="cite" style="color: rgb(0, 0, 0);">
<blockquote type="cite" style="color: rgb(0, 0, 0);">
<pre wrap=""><span class="moz-txt-citetags">> > </span>|-+- policy='round-robin 0' prio=12 status=active
<span class="moz-txt-citetags">> > </span>| |- 0:0:1:1 sdb 8:16 active ready running
<span class="moz-txt-citetags">> > </span>| `- 1:0:1:1 sdd 8:48 active ready running
<span class="moz-txt-citetags">> > </span>`-+- policy='round-robin 0' prio=2 status=enabled
<span class="moz-txt-citetags">> > </span> |- 0:0:0:1 sda 8:0 active ghost running
<span class="moz-txt-citetags">> > </span> `- 1:0:0:1 sdc 8:32 active ghost running
</pre>
</blockquote>
</blockquote>
</blockquote>
Okay!! I never got to this one because I never worked with this
target. Thank you. It is always good to know more. :-)<br>
The secondary paths (or in this case, the ghost paths) are, by
design, supposed to fail on I/O requests. But they should respond to
read_capacity and other commands. More details as described in the
source code itself:<br>
<blockquote> * PATH_GHOST:<br>
* - Use: Only hp_sw and rdac<br>
* - Description: Indicates a "passive/standby" path on
active/passive HP<br>
* arrays. These paths will return valid answers to certain
SCSI commands<br>
* (tur, read_capacity, inquiry, start_stop), but will fail I/O
commands.<br>
* The path needs an initialization command to be sent to it in
order for<br>
* I/Os to succeed.<br>
*<br>
</blockquote>
So going back to this bug reports actual question. If the
multipathed map is working, there's no bug. You could ignore these
scsi errors. This is similar to a faults scenario. At faults, during
the recovery timeo, scsi throws a lot of error messages, which
should be ignored.<br>
<br>
<pre class="moz-signature" cols="72">--
Ritesh Raj Sarraf
RESEARCHUT - <a class="moz-txt-link-freetext" href="http://www.researchut.com">http://www.researchut.com</a>
"Necessity is the mother of invention."
</pre>
</body>
</html>