<div dir="ltr">As long as each backend has a unique name, you can key the type to a list of backend names if there's no useful capabilities to key off. No restart required.<br></div><div class="gmail_extra"><br><div class="gmail_quote">On 14 June 2016 at 10:16, chen ying <span dir="ltr"><<a href="mailto:chenyingkof@outlook.com" target="_blank">chenyingkof@outlook.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div style="font-size:12pt;color:#000000;background-color:#ffffff;font-family:Calibri,Arial,Helvetica,sans-serif">
<p><span></span></p>
<p><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Hi
</span><span style="FONT-SIZE:10pt" lang="EN-US">John,</span></p>
<p><span style="FONT-SIZE:10pt" lang="EN-US"> </span></p>
<p><span style="FONT-SIZE:10pt" lang="EN-US"> </span><span lang="EN-US">User case 1:<br>
The backends in backend-group-1 have SSD disk, more memory . The backend-group-1 can provide higher performance to user.<br>
The other backends in backend-group-2 have HHD disk, more capacity. The backend-group-2 can provide more storage space to user .</span></p>
<p><span style="FONT-FAMILY:'Cambria Math','serif'" lang="EN-US"></span><span style="FONT-FAMILY:'Courier New'" lang="EN-US">Not sure, but we sort of do some of this already via the filter scheduler. An Admin can define various types
(they may be set up based on performance, ssd, spinning-rust etc). Those types are then given arbitrary definitions via a type (again details hidden from end user) and he/she can create volumes of a specific type.</span></p>
<p><span style="FONT-SIZE:10pt" lang="EN-US"> </span></p>
<p style="TEXT-INDENT:21pt"><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Yes, An Admin can arbitrary define various types and he/she can create volumes of a specific type. But we need
to restart our cinder driver after define various types in each driver(If the driver cannot report capabilities by itself). It will not easy to manage for Admin. </span></p>
<p style="TEXT-INDENT:21pt"><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Does Admin could use the concept of dynamically adding/removing backends to backend-group. In this way, we not
need to modify backend configure file(such as: report a capabilities of ssd, spinning-rust etc).We can arbitrary define various types for backend-group, and also he/she can create volumes of a specific type(from backend-group type).</span></p>
<p style="TEXT-INDENT:21pt"><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">So for example I could say "I want these backends with capability XYZ", and many of backends from different
vendors. How to manage these backends by Administrator?</span></p>
<p style="TEXT-INDENT:21pt"><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Currently:</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">1.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Admin need modify backend configure file, let the backend report capability XYZ to filter scheduler.</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">2.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Restart the volume service, make the capability valid</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">3.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Create volume type(test_type) with capability XYZ.</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">4.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">he/she can create volumes of a specific type(test_type)</span></p>
<p><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US"> Now we expect:</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">1.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Admin add backend to backend-group</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">2.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">Create volume type(test_type) with capability XYZ, use frefix(group or something else (group: capability = XYZ)) to distinguish between the backend
capability and the backend-group capability.</span></p>
<p style="MARGIN-LEFT:83.3pt">
<span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">3.<span style="FONT-FAMILY:'Times New Roman';FONT-SIZE:7pt">
</span></span><span style="FONT-FAMILY:'Calibri','sans-serif';COLOR:#1f497d;FONT-SIZE:10.5pt" lang="EN-US">he/she can create volumes of a specific type(test_type)</span></p>
<span></span><br>
<p></p>
</div>
</div>
<br>__________________________________________________________________________<br>
OpenStack Development Mailing List (not for usage questions)<br>
Unsubscribe: <a href="http://OpenStack-dev-request@lists.openstack.org?subject:unsubscribe" rel="noreferrer" target="_blank">OpenStack-dev-request@lists.openstack.org?subject:unsubscribe</a><br>
<a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev" rel="noreferrer" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a><br>
<br></blockquote></div><br><br clear="all"><br>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div>-- <br>Duncan Thomas</div></div></div>
</div>