From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Turner <drakonstein-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: Ceph cluster stability
Date: Tue, 19 Feb 2019 12:26:41 -0500
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To: M Ranga Swami Reddy <swamireddy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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With a RACK failure domain, you should be able to have an entire rack
powered down without noticing any major impact on the clients.  I regularly
take down OSDs and nodes for maintenance and upgrades without seeing any
problems with client IO.

On Tue, Feb 12, 2019 at 5:01 AM M Ranga Swami Reddy <swamireddy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:

> Hello - I have a couple of questions on ceph cluster stability, even
> we follow all recommendations as below:
> - Having separate replication n/w and data n/w
> - RACK is the failure domain
> - Using SSDs for journals (1:4ratio)
>
> Q1 - If one OSD down, cluster IO down drastically and customer Apps
> impacted.
> Q2 - what is stability ratio, like with above, is ceph cluster
> workable condition, if one osd down or one node down,etc.
>
> Thanks
> Swami
> _______________________________________________
> ceph-users mailing list
> ceph-users-idqoXFIVOFJgJs9I8MT0rw@public.gmane.org
> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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<div dir=3D"ltr">With a RACK failure domain, you should be able to have an =
entire rack powered down without noticing any major impact on the clients.=
=C2=A0 I regularly take down OSDs and nodes for maintenance and upgrades wi=
thout seeing any problems with client IO.</div><br><div class=3D"gmail_quot=
e"><div dir=3D"ltr" class=3D"gmail_attr">On Tue, Feb 12, 2019 at 5:01 AM M =
Ranga Swami Reddy &lt;<a href=3D"mailto:swamireddy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org">swamireddy@gm=
ail.com</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"=
margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-lef=
t:1ex">Hello - I have a couple of questions on ceph cluster stability, even=
<br>
we follow all recommendations as below:<br>
- Having separate replication n/w and data n/w<br>
- RACK is the failure domain<br>
- Using SSDs for journals (1:4ratio)<br>
<br>
Q1 - If one OSD down, cluster IO down drastically and customer Apps impacte=
d.<br>
Q2 - what is stability ratio, like with above, is ceph cluster<br>
workable condition, if one osd down or one node down,etc.<br>
<br>
Thanks<br>
Swami<br>
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oreferrer" target=3D"_blank">http://lists.ceph.com/listinfo.cgi/ceph-users-=
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</blockquote></div>

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