#Openstack

Multiqueue in KVM Virtualization: Boosting I/O Performance Preface What is Multiqueue? Advantages of Multiqueue KVM Implementation Reference Multiqueue in KVM Virtualization: Boosting I/O Performance Preface In the realm of virtualization, optimizing I/O performance is a perpetual pursuit. As host systems become more powerful with increasing core counts and faster storage, traditional single-queue I/O models can quickly become a bottleneck, limiting the overall throughput and responsiveness of virtual machines (VMs). [Read More]

Public Cloud Upgrade. Preparations Change Request Customer Engagement Executive management Resource planning Frequent Updates Stage your Upgrade Monitoring Day01 - Infra Upgrade Day02 - Tungsten Fabric (MW01) Day03 - VCP Components (MW02) Day04 - Dataplane - ZONE-01 Compute nodes (MW03) Day05 - Dataplane - ZONE-02 Compute nodes (MW04) QA Statistics References Public Cloud Upgrade. What is the scariest task, a cloud administrator may face, Public Cloud Upgrade. [Read More]

Preface Would you need an Upgrade? Plan the upgrade Methods of upgrades Parallel Cloud Advantages Disadvantages Rolling upgrade Advantages Do an upgrade in Staging Backup Upgrade plan Upgrade Day01 Day02 Customer Feedback Further Reading Preface Upgrading a public cloud to the next stable release is a Nightmare for the Operations Team. We are using Openstack as our cloud software. [Read More]

No valid hosts found Real scenario Oh, yeah here it is Issue Finding Further reading No valid hosts found I am sure, everyone of you found this error in your API call OR Horizon instance intiation. But what is it exactly?, Well the error says no valid hosts found which is clear right? You dont have enough computing resource to launch the new virtual machine. It could be vCPU, vRAM, vDISK. [Read More]

What is Live Migration Why we need a Live Migration Host Failure Maintanance mode Optimal resource usage How a Live migration happening ? Pre-migration Reservation Iterative pre-copy Stop and Copy Commitment Pitfalls Abort ? Futher reading What is Live Migration Live-migrating an instance means moving its virtual machine to a different OpenStack Compute server while the instance continues running. When you are operating a public cloud OR private cloud you need to do this for many reasons. [Read More]

Preface Core services may not running Two different host types No Shared volume No enough Quota Apparmor in place The source compute host swapped No valid host found Further reading Preface Recently I had faced an interesting question during an Interview. Question was, One of the virtual machine is in error state, how will you troubleshoot?. Well, thats a general question and all of them went through it atleast once? [Read More]

What is an Overcommit in cloud ? Overcommitting Memory Overcommitting CPU Why its important in a Public Cloud Where are the Overcommit values in Openstack Well, I have a very special requirement Solution Create the aggregate Add your computes to this Aggregate Setting up Overcommit values to this particular Aggregate How the Guest VM know, i should go to this Aggregate Inject Flavor metadata Check the flavor now Add few filters in nova Disable the current allocation from nova Restart nova Workflow Further Reading What is an Overcommit in cloud ? [Read More]

What is Python Virtualenvironment Installation Install pip Install needed Python modules Set a Directory for your Environments Add it on your bashprofile Testing the virtualenvironment Activate and Deactivate the environment Remove the Virtualenvironment Futher Reading What is Python Virtualenvironment Python applications will often use packages and modules that don’t come as part of the standard library. Applications will sometimes need a specific version of a library, because the application may require that a particular bug has been fixed or the application may be written using an obsolete version of the library’s interface. [Read More]

Courtesy Preface Assumptions Solution Import Route Target Security Group Futher Reading Courtesy Bytes around me :-) Preface Sharing Private network is a common use case in Cloud Environment. Normally RBAC will help you to achieve. Since Newton release, this feature is Available. But the question is which SDN you are using in your Environment. If you are using Opencontrail 3.2 as SDN, you cannot go with RBAC. Assumptions Openstack Release Ocata Opencontrail 3. [Read More]

Courtesy Preface Use Case Implementation New Routing Table Add Policy Rules Flush the routing cache Testing Rules Further Reading Courtesy Tutorial credit goes to [Omar Hamad ] (https://www.linkedin.com/in/omermahgoub/) the real Architect I have seen in last few years. Working with him for the past 3 Years, and learned a Lot. We are going to miss u :( Preface When configuring a Linux host with multiple interface, each with its own default gateway, ensuring route symmetric is a bet challenging for any given pair of endpoint. [Read More]