<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Title" content="">
<meta name="Keywords" content="">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:Calibri;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal;
font-family:Calibri;
color:windowtext;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:Calibri;
color:windowtext;}
span.msoIns
{mso-style-type:export-only;
mso-style-name:"";
text-decoration:underline;
color:teal;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style>
</head>
<body bgcolor="white" lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-family:"Times New Roman"">><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> Hi Openstack operators,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> Most Openstack HA deployment use 3 node database cluster, 3 node rabbitMQ cluster and 3 Controllers.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> I am wondering whether there are any studies done that show the pros and cons of co-locating database and messaging service with the Openstack control services.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> In other words, I am very interested in learning about advantages and disadvantages, in terms of ease of deployment,
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> upgrade and overall API performance, of having 3 all-in-one Openstack controller over a more distributed deployment model.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">In general, a host with less running services is easier to troubleshoot.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">However, there is no fundamental issue with sharing mysql/rabbit on a single controller assuming the host is quick enough.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">For the OpenStack API services I would highly recommend “splitting” things up.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It does not necessarily need to be on different physical hosts but at least use something to prevent package dependencies between the different OpenStack components (virtualenv/containers/vms).
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">If you do not do this it makes upgrades of an individual component on a node near impossible.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Cheers,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Robert van Leeuwen<o:p></o:p></span></p>
</div>
</body>
</html>