<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Jul 13, 2016 at 10:29 AM, Dmitry Melekhov <span dir="ltr"><<a href="mailto:dm@belkam.com" target="_blank">dm@belkam.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div>13.07.2016 08:56, Pranith Kumar
Karampuri пишет:<br>
</div><div><div class="h5">
<blockquote type="cite">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed, Jul 13, 2016 at 10:23 AM,
Dmitry Melekhov <span dir="ltr"><<a href="mailto:dm@belkam.com" target="_blank"></a><a href="mailto:dm@belkam.com" target="_blank">dm@belkam.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div>13.07.2016 08:46, Pranith Kumar Karampuri пишет:<br>
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<span>
<blockquote type="cite">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed, Jul 13, 2016 at
10:10 AM, Dmitry Melekhov <span dir="ltr"><<a href="mailto:dm@belkam.com" target="_blank"></a><a href="mailto:dm@belkam.com" target="_blank">dm@belkam.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div>13.07.2016 08:36, Pranith Kumar
Karampuri пишет:<br>
</div>
<span>
<blockquote type="cite">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed,
Jul 13, 2016 at 9:35 AM, Dmitry
Melekhov <span dir="ltr"><<a href="mailto:dm@belkam.com" target="_blank"></a><a href="mailto:dm@belkam.com" target="_blank">dm@belkam.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">13.07.2016
01:52, Anuradha Talur пишет:<span><br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <br>
----- Original Message
-----<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
From: "Dmitry Melekhov"
<<a href="mailto:dm@belkam.com" target="_blank"></a><a href="mailto:dm@belkam.com" target="_blank">dm@belkam.com</a>><br>
To: "Pranith Kumar
Karampuri" <<a href="mailto:pkarampu@redhat.com" target="_blank"></a><a href="mailto:pkarampu@redhat.com" target="_blank">pkarampu@redhat.com</a>><br>
Cc: "gluster-users" <<a href="mailto:gluster-users@gluster.org" target="_blank"></a><a href="mailto:gluster-users@gluster.org" target="_blank">gluster-users@gluster.org</a>><br>
Sent: Tuesday, July 12,
2016 9:27:17 PM<br>
Subject: Re:
[Gluster-users] 3.7.13,
index healing broken?<br>
<br>
<br>
<br>
12.07.2016 17:39,
Pranith Kumar Karampuri
пишет:<br>
<br>
<br>
<br>
Wow, what are the steps
to recreate the problem?<br>
<br>
just set file length to
zero, always
reproducible.<br>
<br>
</blockquote>
If you are setting the
file length to 0 on one of
the bricks (looks like<br>
that is the case), it is
not a bug.<br>
<br>
Index heal relies on
failures seen from the
mount point(s)<br>
to identify the files that
need heal. It won't be
able to recognize any file<br>
modification done directly
on bricks. Same goes for
heal info command which<br>
is the reason heal info
also shows 0 entries.<br>
</blockquote>
<br>
</span> Well, this makes
self-heal useless then- if any
file is accidently corrupted
or deleted (yes! if file is
deleted directly from brick
this is no recognized by idex
heal too), then it will not be
self-healed, because self-heal
uses index heal.<span><br>
</span></blockquote>
<div><br>
</div>
<div>It is better to look into
bit-rot feature if you want to
guard against these kinds of
problems.<br>
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</div>
</div>
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</blockquote>
<br>
</span> Bit rot detects bit problems, not
missing files or their wrong length, i.e.
this is overhead for such simple task.<br>
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</blockquote>
<div><br>
</div>
<div>It detects wrong length. Because checksum
won't match anymore.<br>
</div>
</div>
</div>
</div>
</blockquote>
<br>
</span> Yes, sure. I guess that it will detect missed
files too. But it needs far more resources, then just
comparing directories in bricks?<span><br>
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<div><br>
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<div>What use-case you are trying out is
leading to changing things directly on the
brick?<br>
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</div>
</div>
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</blockquote>
</span> I'm trying to test gluster failure tolerance and
right now I'm not happy with it...<br>
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</blockquote>
<div><br>
</div>
<div>Which cases of fault tolerance are you not happy with?
Making changes directly on the brick or anything else as
well?<br>
</div>
<br>
</div>
</div>
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</blockquote></div></div>
I'll repeat:<span class=""><br>
As I already said- if I for some reason ( real case can be only by
accident ) will delete file this will not be detected by self-heal
daemon, and, thus, will lead to lower replication level, i.e. lower
failure tolerance. <br></span></div></blockquote><div><br>To prevent such accidents you need to set selinux policies so that files under the brick are not modified by accident by any user. At least that is the solution I remember when this was discussed 3-4 years back.<br></div></div><br>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr">Pranith<br></div></div>
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