Category: Linux

Posted in Cloud, Linux, network

Quick Steps to build your own lab using VirtualBox and Vagrant

Posted on by Vishwanath Mule

Many times we need test lab which includes two or more virtual machines and which should be built quickly on our laptop and test different scenarios of docker, Kubernetes and Ansible and tear down once done.

I used to install VirtualBox on my laptop and then install CentOS manually and then clone it for two or three VMs, this also works fine but it is time-consuming as my aim was to learn the docker, Kubernetes concepts or test Ansible playbooks, once done tear down the setup and start new one for other test cases.

There is one simple solution out there where we can use VirtualBox and Vagrant to set up a multinode environment using the configuration file and start the lab in a few mins.

I have summarized a few steps to quickly set up your own lab with VirtualBox and Vagrant.

You can create as many virtual machines you want but you need enough RAM on your laptop/desktop.

1. Download the VirtualBox software using the following link. Just check the latest/stable release wget https://download.virtualbox.org/virtualbox/6.0.4/VirtualBox-6.0-6.0.4_128413_el7-1.x86_64.rpm

      Install the VirtualBox #rpm -ivh VirtualBox-6.0-6.0.4_128413_el7-1.x86_64.rpm

2. Download the Vagrant setup using the link

     wget https://releases.hashicorp.com/vagrant/2.2.4/vagrant_2.2.4_x86_64.rpm

       
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Posted in Cloud, Linux

Quick Steps for install KVM hypervisor

Posted on by Vishwanath Mule

This post describe quick steps to install KVM hypervisor on CentOS7. KVM (Kernel based Virtual Machine) is opensource hypervisor, lightweight and works/fits well into cloud.

For your personal lab you can use KVM hypervisor layer and utilize hardware for creation of multiple VMs. KVM support both linux and windows based VMs.

Check whether system CPU supports Hardware Virtualization. #grep -E ‘{vmx|svm}’ /proc/cpuinfo

if you get vmx or svm in output then you are good to go ahead otherwise your CPU doesn’t support virtualization.

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Posted in Cloud, Linux, Openstack

Basic Cinder (volume) service functionality in Openstack – Part2

Posted on by Vishwanath Mule

We saw volume creation with related issues and probable solutions.

Now we will see volume attach to VM. Create partition on it. Remove it and detach volume from VM.

Attach created volume to testvm. Following is command-line requirement for cinder volume-attach.

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Volume ID will get it from cinder-list use auto to autoassign the new device.

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You can check volume status is changed to in-use now and also changed attached with VM ID.

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Continue reading “Basic Cinder (volume) service functionality in Openstack – Part2” →

Posted in Cloud, Linux, Openstack

Basic Cinder (volume) service functionality in Openstack – Part1

Posted on by Vishwanath Mule

In this post I am going to show you basic functionality of openstack cinder (volume) service functionality by creating volume on internal storage. Attaching that volume to VM. Create partition on that volume in client machine and test partition remove and detaching volume from VM.

Lets take one running state vm for cinder testing as we can do this operation on the fly. I have one VM name testvm.

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Check the disk and partitions on the VM. I can access the testvm using private IP and public IP. Lets access it using private IP using unique network namespace.

First check private-net network ID and test the ping to private IP of VM using network namespace. For more details about basic networking in openstack check my last blog posts.

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Posted in Linux, Openstack

Failed to start OpenStack Identity Service (code-named Keystone).

Posted on by Vishwanath Mule

When you installed Openstack using packstack you might have faced openstack-keystone service issue. When try it to restart it fails with code-name keystone error.

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I have done some research on it and found the solution.

The issue is with Openstack Keystone Service which we have configured using httpd deamon in answers.cfg file ( configuration file used to install Openstack using packstack)

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Now openstack-keystone service will not start as http service is already in started mode and we haven’t created any relation between openstack-keystone and http service.

So to start openstack-keystone service we have to create symbolic link and point openstack-keystone service to http service.

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Posted in Linux, Uncategorized

Graphical/Desktop UI for Centos 7/RHEL 7

Posted on by Vishwanath Mule

Many times we need graphical UI to open/run some applications. So following are simple and quick steps to create graphical UI on Centos7/RHEL7.

First check you have yum repository configured to access local or internet repository

#yum repolist

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Graphical UI filesets will install in group so that all required/dependent filesets will install automatically. Check all available groups in yum repository using group list

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Posted in Linux, Openstack

Multinode Openstack Installation on Centos 7/RHEL 7

Posted on by Vishwanath Mule

This post describing multinode OpenStack installation on centos7/rhel7 for Liberty release. If you want to do single node installation please refer my earlier post.

We are installing OpenStack onto 3 nodes controller,compute and network using packstack utility

Following is 3 node Openstack Architecture and related Openstack services running on respective nodes. I am using two network one is management network of 192.168.56.* which is used for internal communication between nodes and one external network used to assign public IP to VM and to access instances/VM from outside. I am also using NATed DHCP ip on each nodes to download required filesets from internet.

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Posted in Linux, Openstack

Openstack Liberty install using packstack on Centos 7/RHEL 7

Posted on by Vishwanath Mule

This post is a quickstart guide to install OpenStack Liberty release using packstack on CentOS7.

This is very basic POC setup where all components will be installed on one node only. I will create another post for multinode installation setup.

  1. Install CentOS using minimal install Software Selection.

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Continue reading “Openstack Liberty install using packstack on Centos 7/RHEL 7” →

Posted in Linux, network

Network Configuration in RHEL 7/Centos 7

Posted on by Vishwanath Mule

In this post I am going to show how to do network configuration in rhel7/centos7. We have ip command introduced in linux way back but we never used it. In this post we will use ip related commands which isnot easy to use as it has many options need to provide to get relevant output.

to see IP address details normally we used ifconfig command we check the same using ip addr show command.

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Here we an see ipv4 address of eth0 interface along with ipv6 address and network UP status and mtu size.
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