<div dir="auto">Hi,<div dir="auto"><br></div><div dir="auto">We <span style="background-color:rgb(255,255,255);color:rgb(12,13,14);font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit">have an OpenStack Environment with 5000+ VMs running currently. I want to apply some common Security Group to all my running VMs.</span></div><ul style="margin-top:0px;margin-right:0px;margin-left:2em;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:15px;vertical-align:baseline;list-style-position:initial;color:rgb(12,13,14);background-color:rgb(255,255,255)"><li style="margin-top:0px;margin-right:0px;margin-left:0px;padding:0px;border:0px;font:inherit;vertical-align:baseline">Common Security Group (SEC_GRP_COMMON) has around 700 rules.</li><li style="margin-top:0px;margin-right:0px;margin-left:0px;padding:0px;border:0px;font:inherit;vertical-align:baseline">This Security Group (SEC_GRP_COMMON) has been shared to all the OpenStack Projects using Role-Based Access Control (RBAC).</li><li style="margin:0px;padding:0px;border:0px;font:inherit;vertical-align:baseline">Wanted to apply this Security Group (SEC_GRP_COMMON) to all the running VMs in the Cloud</li></ul><p style="margin-top:0px;margin-right:0px;margin-left:0px;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit;vertical-align:baseline;color:rgb(12,13,14);background-color:rgb(255,255,255)"><strong style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;line-height:inherit;font-family:inherit;font-size:inherit;vertical-align:baseline">Question 1</strong>: With the above scenario, what will happen if I attach this Security Group(with 700+ rules) to all the 5000+ VMs? Will there be any performance issue/impact for the same (CPU utilization, Memory etc. in the Compute Server or Performance issues in application running in the VMs)</p><p style="margin:0px;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit;vertical-align:baseline;color:rgb(12,13,14);background-color:rgb(255,255,255)"><strong style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;line-height:inherit;font-family:inherit;font-size:inherit;vertical-align:baseline">Question 2</strong>: Is there any recommendations or benchmark data for maximum number of rules in the Security Group in OpenStack cloud?</p><p style="margin:0px;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit;vertical-align:baseline;color:rgb(12,13,14);background-color:rgb(255,255,255)"><br></p><p style="margin:0px;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit;vertical-align:baseline;color:rgb(12,13,14);background-color:rgb(255,255,255)">Thanks,</p><p style="margin:0px;padding:0px;border:0px;line-height:inherit;font-family:"helvetica neue",helvetica,arial,sans-serif;font-size:inherit;vertical-align:baseline;color:rgb(12,13,14);background-color:rgb(255,255,255)">Dhana</p></div>