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Date: Mon, 10 Jun 2013 13:41:13 -0400
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 <CAENxBwx0U_ZWq3fD2ekh10z2tLNR5AJ-bWzpDTWWprK1T4WWdQ@mail.gmail.com>
Subject: Re: Data Loss/Missing With Cassandra
From: Edward Capriolo <edlinuxguru@gmail.com>
To: "user@cassandra.apache.org" <user@cassandra.apache.org>
Content-Type: multipart/alternative; boundary=089e016347fa744ca304ded049dc

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To recover it would be to dump everything then re-insert everything.

Another option would be to return all nodes to whatever tokens they were
before the switches, since the old data is still there.

Either way both recovery options are long,painful, and a good amount of
manual steps. I would not want to do either one.


On Mon, Jun 10, 2013 at 12:39 PM, Nimi Wariboko Jr
<nimiwaribokoj@gmail.com>wrote:

> How can I recover that data? Can I assume they are still in the sstables?
> Would doing a sstable2json then reading and reinserting be an optimal
> solution?
>
> On Monday, June 10, 2013 at 9:18 AM, Tyler Hobbs wrote:
>
>
> On Sun, Jun 9, 2013 at 3:19 PM, Nimi Wariboko Jr <nimiwaribokoj@gmail.com>wrote:
>
> If I had to do a repair after upping the RF, than that is probably what
> caused the data loss. Wish I had been more careful.
>
> I'm guessing the data is irrevocably lost, I didn't make any any snapshots.
>
> Would it be possible to figure out if only a certain part of the ring was
> effected? That would be helpful in figuring out what data was lost.
>
> I've done a full repair now, so I'm also guessing that inconsistent data
> is now completely gone as well, right?
>
>
> Cassandra doesn't remove data automatically (partially to help prevent
> data loss in cases like this).  The original node will still have the full
> set of data unless you have run a cleanup operation (nodetool cleanup) on
> it.
>
>
> --
> Tyler Hobbs
> DataStax <http://datastax.com/>
>
>
>

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<div dir=3D"ltr"><div><div>To recover it would be to dump everything then r=
e-insert everything.<br><br></div>Another option would be to return all nod=
es to whatever tokens they were before the switches, since the old data is =
still there.<br>
<br></div>Either way both recovery options are long,painful, and a good amo=
unt of manual steps. I would not want to do either one.<br></div><div class=
=3D"gmail_extra"><br><br><div class=3D"gmail_quote">On Mon, Jun 10, 2013 at=
 12:39 PM, Nimi Wariboko Jr <span dir=3D"ltr">&lt;<a href=3D"mailto:nimiwar=
ibokoj@gmail.com" target=3D"_blank">nimiwaribokoj@gmail.com</a>&gt;</span> =
wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
                <div style=3D"font-family:Helvetica;font-size:13px">How can=
 I recover that data? Can I assume they are still in the sstables? Would do=
ing a sstable2json then reading and reinserting be an optimal solution?</di=
v>
<div><div><br></div></div>
                =20
                <p style=3D"color:#a0a0a8">On Monday, June 10, 2013 at 9:18=
 AM, Tyler Hobbs wrote:</p>
                <blockquote type=3D"cite" style=3D"border-left-style:solid;=
border-width:1px;margin-left:0px;padding-left:10px">
                    <span><div><div><div dir=3D"ltr"><div><br><div>On Sun, =
Jun 9, 2013 at 3:19 PM, Nimi Wariboko Jr <span dir=3D"ltr">&lt;<a href=3D"m=
ailto:nimiwaribokoj@gmail.com" target=3D"_blank">nimiwaribokoj@gmail.com</a=
>&gt;</span> wrote:<br>
<blockquote type=3D"cite"><div><div>
                </div><div>If I had to do a repair after upping the RF, tha=
n that is probably what caused the data loss. Wish I had been more careful.=
</div><div><br></div><div>I&#39;m guessing the data is irrevocably lost, I =
didn&#39;t make any any snapshots.</div>


<div><br></div><div>Would it be possible to figure out if only a certain pa=
rt of the ring was effected? That would be helpful in figuring out what dat=
a was lost.</div><div><br></div><div>I&#39;ve done a full repair now, so I&=
#39;m also guessing that inconsistent data is now completely gone as well, =
right?</div>


</div></blockquote></div><br>Cassandra doesn&#39;t remove data automaticall=
y (partially to help prevent data loss in cases like this).=A0 The original=
 node will still have the full set of data unless you have run a cleanup op=
eration (nodetool cleanup) on it.<br>


<br clear=3D"all"><span class=3D"HOEnZb"><font color=3D"#888888"><br>-- <br=
><font color=3D"#888888">Tyler Hobbs<span></span><br>
<a href=3D"http://datastax.com/" target=3D"_blank">DataStax</a><br></font>
</font></span></div></div>
</div></div></span>
                =20
                =20
                =20
                =20
                </blockquote>
                =20
                <div>
                    <br>
                </div>
            </blockquote></div><br></div>

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