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Tag: DevOps

  • Automating Kubernetes deployment on VMs using Ansible

    Automating Kubernetes deployment on VMs using Ansible

    In this post, we will discuss automating Kubernetes deployment using Ansible.

    In my example, I have used CentOS VMs (on VMware) for deploying Kubernetes. But technically Kubernetes deployment steps don’t differ irrespective of the platform you use.

    Before getting started to make sure you have

    • Ansible server up and running on the network. Also, make sure Ansible can reach the VMware environment.
    • Make sure you’ve added Ansible server SSH authentication keys into VMware virtual machine before converting the same into the template. Follow this blog post for steps.

    Once you have the pre-requisites in place follow the below steps.

    Step 1 – Clone my GitHub repository which consists of required playbooks and instructions.

    [root@alb-ansible dw-pm-csi]# git clone https://github.com/waghmaredb/ansible-k8s
Cloning into 'ansible-k8s'…
remote: Enumerating objects: 41, done.
remote: Counting objects: 100% (41/41), done.
remote: Compressing objects: 100% (40/40), done.
remote: Total 41 (delta 12), reused 0 (delta 0), pack-reused 0
Unpacking objects: 100% (41/41), done.
[root@alb-ansible dw-pm-csi]# cd ansible-k8s/
[root@alb-ansible ansible-k8s]# ls
k8s-deployment.yml README.md

    Step 2 – Edit k8s-deployment.yml file and edit below lines from VARS

    common environment details
#ntp_server: - Replace with your NTP server IP/hostname
domain: "" - Replace with your DOMAIN NAME
dns_server: - Replace with your DNS server IP/hostname
vmware environment details
vcenter_ip: - Replace with your vCenter server IP/hostname
vcenter_username: - Replace with vCenter admin account username
vcenter_password: - Replace with vCenter admin account password
vmware_datacenter: - Replace with VMware datacenter you want to use
vmware_cluster: - Replace with VMware cluster you want to use
vm_network: "" - Replace with VM network you want kubernetes VMs to connect
k8s_vm_folder: - Replace with VM folder in which you want to place kubernetes VMs
k8s_template_name: - Replace with VMware CentOS template name
K8S environment details
k8s_master_ip: 192.168.172.100 - Replace IP address with kubernetes master server IP address you want to use
k8s_network_netmask: 255.255.255.0 - Replace subnet mask with netmask of kubernetes network
k8s_network_gateway: 192.168.172.1 - Replace gateway with kubernetes network gateway
k8s_node1_ip: 192.168.172.101 - Repalce IP address with kubernetes node IP address
#k8s_node2_ip: 192.168.1.102
#k8s_node3_ip: 192.168.1.103
#k8s_node4_ip: 192.168.1.104
#k8s_node5_ip: 192.168.1.105
#k8s_node6_ip: 192.168.1.106
#k8s_node7_ip: 192.168.1.107
#k8s_node8_ip: 192.168.1.108

    Step 3 – Edit the /etc/ansible hosts file and insert the Kubernetes environment details. Make sure IP address details are inline with your Kubernetes environment 

    [kube_cluster1]
k8s-master ansible_host=192.168.172.100 ansible_user=root
worker1 ansible_host=192.168.172.101 ansible_user=root
worker2 ansible_host=192.168.172.102 ansible_user=root
worker3 ansible_host=192.168.172.103 ansible_user=root
worker4 ansible_host=192.168.172.104 ansible_user=root

[master]
k8s-master ansible_host=192.168.172.100 ansible_user=root

[worker]
worker1 ansible_host=192.168.172.101 ansible_user=root
worker2 ansible_host=192.168.172.102 ansible_user=root
worker3 ansible_host=192.168.172.103 ansible_user=root
worker4 ansible_host=192.168.172.104 ansible_user=root

    Step 4 – Run the k8s-deployment.yml playbook.

  • REST API and DellEMC Storage Part 3 – Unity

    REST API and DellEMC Storage Part 3 – Unity

    This blog post is 3rd part of REST API with DellEMC Storage blog series.

    • In the first part of this blog series, we discussed what is REST API and different usage options
    • Second part was about managing DellEMC PowerMax storage arrays using REST API

    In this post, we will discuss how you can use manage DellEMC Unity storage using REST API. We will be using the Postman tool during the entire blog series. So let’s get started with automating the DellEMC Unity storage system.

    The DellEMC Unity REST API Background

    DellEMC Unity is of the most user-friendly storage systems. The most common management tools for Unity systems are

    • Unisphere UI (Embedded) – An HTML5 graphical user interface used to manage Dell EMC Unity systems
    • Unisphere Command Line Interface (UEMCLI) – UEMCLI allows a user to perform tasks on the storage system by typing commands instead of using the graphical user interface

    The Dell EMC Unity includes complete REST API support, providing a developer-friendly way to manage Dell EMC Unity systems and automate various tasks.

    Dell EMC Unity’s REST API fully supports all the management tasks that a user can perform in the Unisphere GUI. Dell EMC Unity’s REST API response formats all communication in JSON notation. Users can send REST API requests using their favorite REST API tools to manage Dell EMC Unity systems in their environment. This provides flexibility in management and opens possibilities for more complex operations.

    DellEMC Unity Management Options

    Assessing DellEMC Unity’s REST API

    Once a Unity system is up and running, users can navigate to the following web addresses to get access to the REST API documentation:

    REST API Programmer’s Guide – https://{{unisphere_management_address}}/apidocs/programmers-guide/index.html

    REST API Reference Guide – https://{{unisphere_management_address}}/apidocs/index.html

    DellEMC Unity’s REST API is available via Unisphere running on the array via the following Base URL.

    https://{{unisphere_management_address}}/api

    • {{unisphere_management_address}} – Replace with IP Unisphere IP address or hostname

    Supported DellEMC Unity REST API Operations

    DellEMC Unity’s REST API supports the following types of REST calls.

    • GET – Get information on objects. For example – Get Unity storage system’s details
    • POST – Create an Object. For example – Create new LUN/s
    • PUT – Making changes to an objects. For example – Change size of the existing LUN
    • DELETE – Remove an object. For example – Delete existing LUN/s

    Usually the REST client (like Postman) can be used to help figure out what REST calls you want to run.

    Building your REST API calls

    Now let’s get started with creating REST API calls. In this example we will create sample REST API call to list all the available storage pools.

    Before we get started make sure you’ve Postman installed and Unisphere is reachable.

    • Open Postman and click on New. Under new drop-down, select Request
    DellEMC Unity REST API – Postman tool GUI – 1
    • In New Request pop-up enter Request name, Description (optional) and Name of the Collection. Then click on Save.
    DellEMC Unity REST API – Postman tool GUI – 2
    • Click on the request type drop-down and select GET.
      • Please note that we are selecting GET because is this example we are creating sample REST API call to list all the available storage pools.
      • This option will be different based on type of REST API operation
    DellEMC Unity REST API – Postman tool GUI – 3
    • Enter below Request URL
      • 1.1.1.1 – Replace with Unisphere IP address/hostname

    https://1.1.1.1/api/types/pool/instances

    DellEMC Unity REST API – Postman tool GUI – 4
    • Click on the Authorization. Enter Unisphere Username and Password.
    DellEMC Unity REST API – Postman tool GUI – 5
    • Note that Unity REST API GET request needs below 3 headers. Click on Headers and enter below header details as shown in the screenshot. Then click Send
      • Accept – application/json
      • Content-type – application/json
      • X-EMC-REST-CLIENT – true
    DellEMC Unity REST API – Postman tool GUI – 5
    • In the Postman Response section you’ll see REST API response. In this case you’ll see list of all the storage pools in Unity array.
    DellEMC Unity REST API – Postman tool GUI – 6

    Additionally please note that POST/PUT/DELETE requests need one additional Header – EMC-CSRF-TOKEN. This token is generated using GET request.

    So, let’s create one POST request for creating new LUN.

    • Follow above-listed GET request steps. Click on Headers under GET Response. Copy the EMC-CSRF-TOKEN from the Headers
    DellEMC Unity REST API – Postman tool GUI – 7
    • Now click on New and Under new drop-down, select Request (screenshot in GET request steps)
    • In New Request pop-up enter Request name, Description (optional) and Name of the Collection. Then click on Save. (screenshot in GET request steps)
    • Click on the request type drop-down and select POST.
      • Please note that we are selecting POST because is this second example we are creating REST API call to create new LUN.
    • Click on the Authorization. Enter Unisphere Username and Password.
    • Under Params enter below details.
      • Name – Name of the LUN
      • Pool – Storage Pool in which LUN will be created
      • Size – LUN size
    DellEMC Unity REST API – Postman tool GUI – 7
    • Click on Headers and enter below header details as shown in the screenshot. Then click Send
      • Accept – application/json
      • Content-type – application/json
      • X-EMC-REST-CLIENT – true
      • EMC-CSRF-TOKEN – Copied from GET response
    DellEMC Unity REST API – Postman tool GUI – 8

    Dell EMC and REST API – Way Forward

    I hope this clarifies many basics for getting started with REST API and DellEMC Unity storage. You might also have understood that creating creating valid URLs is very important aspect of using REST API. Having this in mind we have created ready Postman collection for DellEMC Unity storage. Here’s the GitHub link to the repository. Feel free to download and share.

    Below are the additional resources available for taking REST API usage to next level.

    I hope this post will get you started with your Dell EMC Unity automation journey.

  • REST API and DellEMC Storage Part 2 – PowerMax

    REST API and DellEMC Storage Part 2 – PowerMax

    This blog post is 2nd part of REST API with DellEMC Storage blog series. In the first part of this blog series, we discussed what is REST API and different usage options. I highly encourage you to go through the first part before you get started with this post.

    In this post, we will discuss how you can use manage DellEMC PowerMax storage using REST API. We will be using the Postman tool during the entire blog series. So let’s get started with automating the DellEMC PowerMax storage system.

    The PowerMax REST API Background

    There are many different ways to manage the PowerMax storage system. You can refer to this link for more details around each. Traditionally many customers using the VMAX family systems are using the Solutions Enabler tool. This is a comprehensive tool that allows storage administrators to automate many different storage tasks using scripting (Bash, Perl, Shell scripts, etc.).

    PowerMax Unisphere GUI is HTML5 based management interface, it’s beautiful and functional and provides a web-based interactive experience for users.  Unisphere has a lot of automation baked in, and it’s intuitive wizards eliminate complexity and can often provide the right amount of automation for organizations where there isn’t a lot of change. With Unisphere version 8 everything you can do in the GUI is supported using REST API.

    DellEMC PowerMax Management Options

    Assessing DellEMC PowerMax REST API

    DellEMC PowerMax’s REST API is available via Unisphere (installed or embedded) running on the array via the following Base URL.

    https://{{unisphere_management_address}}:{{8443}}/univmax/restapi/{{version}}

    • {{unisphere_management_address}} – Replace with IP Unisphere IP address or hostname
    • {{8443}} – Default port of Unisphere. Change this as per your environment
    • {{version}} – Replace this with Unisphere version. For Unisphere version 9, replace as 90

    Supported DellEMC PowerMax REST API Operations

    Unisphere for PowerMax’s REST API supports the following types of REST calls.

    • GET – Get information on objects. For example – list all the PowerMax serial numbers managed using Unisphere
    • POST – Create an Object. For example – Create new LUN/s
    • PUT – Making changes to an objects. For example – Change size of the existing LUN
    • DELETE – Remove an object. For example – Delete existing LUN/s

    Usually the REST client (like Postman) can be used to help figure out what REST calls you want to run.

    Building your REST API calls

    Now let’s get started with creating REST API calls. In this example we will create sample REST API call to list all the available SRPs.

    Before we get started make sure you’ve Postman installed and Unisphere is reachable.

    • Open Postman and click on New. Under new drop-down, select Request
    DellEMC PowerMax REST API – Postman tool GUI – 1
    • In New Request pop-up enter Request name, Description (optional) and Name of the Collection. Then click on Save.
    DellEMC PowerMax REST API – Postman tool GUI – 2
    • Click on the request type drop-down and select GET.
      • Please note that we are selecting GET because is this example we are creating sample REST API call to list all the available SRPs.
      • This option will be different based on type of REST API operation
    DellEMC PowerMax REST API – Postman tool GUI – 3
    • Enter below Request URL
      • 1.1.1.1 – Replace with Unisphere IP address/hostname
      • 000123456789 – Replace with Serial number of PowerMax array

    https://1.1.1.1:8443/univmax/restapi/90/sloprovisioning/symmetrix/000123456789/srp

    DellEMC PowerMax REST API – Postman tool GUI – 4
    • Click on the Authorization. Enter Unisphere Username and Password. Then click Send
    DellEMC PowerMax REST API – Postman tool GUI – 5
    • In the Postman Response section you’ll see REST API response. In this case you’ll see list of all the SRPs in PowerMax array.
    DellEMC PowerMax REST API – Postman tool GUI – 6

    Dell EMC and REST API – Way Forward

    I hope this clarifies many basics for getting started with REST API and DellEMC storage. You might also have understood that creating creating valid URLs is very important aspect of using REST API. Having this in mind we have created ready Postman collection for DellEMC PowerMax storage. Here’s the GitHub link to the repository. Feel free to download and share.

    Below are the additional resources available for taking REST API usage to next level.

    1. REST API client for Unisphere – This is simple GUI tool which allows you to to construct REST API calls. Best part of this tool is having a tree view of all resources on the Unisphere to which the users can navigate through to select the desired REST call.
    2. DellEMC PowerMax REST API Concepts and Programmer’s Guide – This link has REST API document for Dell EMC PowerMax array.

    I hope this post will get you started with your Dell EMC PowerMax automation journey.

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  • REST API and DellEMC Storage Part 1 – Introduction

    REST API and DellEMC Storage Part 1 – Introduction

    This post is the first post of multi-part blog series to understand and use RestAPI with DellEMC XtremIO storage.

    REST API with Dell EMC

    REST stands for Representational State Transfer. REST provides access to resources (DellEMC XtremIO resources in our case) on a tree-like structure. REST uses HTTP/S for communication and replies on HTTP’s CRUD operations, which are GET, POST, PUT, DELETE. REST is stateless, which means it does not store application state information. Since REST is stateless client responses are self-documenting. For this introduction post we will talk about XtremIO, but note that each storage system has different URNs.

    REST enables each XtremIO resource (like volumes, initiator groups, etc) having its own URI (Uniform Resource Identifier). Typically REST response is received in JSON or XML format. In the case of XtremIO responses are in JSON format.

    XtremIO REST API can be accessed using the below option

    • REST Clients – Like Postman
    • CLI – Using tools like CURL
    • Programming – Using Python, Ruby, etc.

    Since XtremIO storage array is having API-first design, it allows all the operations using REST which can be done using CLI/GUI.

    Connecting to XtremIO using REST API

    XtremIO is a scale-out storage architecture and has out-of-band management server – aka XMS. You can refer to below high level diagram to check your connectivity.

    DellEMC XtremIO REST API – High Level Connectivity

    Below are the supported types of REST API with XtremIO.

    XtremIO – Supported REST API commands

    Below is the example and details of using XtremIO REST API using CURL 

    # curl -k --request GET https://<user>:<pass>@1.1.1.1/api/json/v2/types
    • -k – Allow insecure SSL connection. This is needed in case you’ve self-signed certificate.
    • –request GET – This is the REST API request type.
    • https://:@1.1.1.1/api/json/v2/types – URI
      • https:// – Protocol used for REST API
      • <user>:<pass> – XtremIO XMS credentials
      • @1.1.1.1 – XtremIO XMS IP address
      • /api/json/v2/types – API Path

    In next post we will discuss on using REST API with Dell EMC storage systems

  • Ansible with DellEMC Storage: Part 4 – DellEMC PowerMax Ansible Modules

    Ansible with DellEMC Storage: Part 4 – DellEMC PowerMax Ansible Modules

    This blog is the continuation of Ansible with DellEMC storage multi-part blog. 

    • In Part 1 of this series, we discussed getting started with the installation of dependencies for the Ansible and DellEMC Ansible module, followed by Ansible installation.
    • Part 2 was about the high-level basics of Ansible to get you started quickly.
    • Part 3 was getting you through the DellEMC PowerMax Ansible module installation.

    In this 4th part, we will discuss available Ansible modules for DellEMC
    PowerMax storage. Note that this blog is based on DellEMC PowerMax Ansible Module version 1.1 (Released in Dec 2019).

    Before you get started with automating DellEMC PowerMax make sure that you’re running below software versions

    • Software Version – 5978.221.221 / 5978.444.444
    • Unisphere version –  9.0 / 9.1

    Below depicted are the available Ansible modules for DellEMC PowerMax version 1.1.

    DellEMC PowerMax Ansible Module v1.1 – List of available modules

    Before you get started it’s important to understand the purpose of each module. Some of the modules can be data disruptive. You can get more details on each function on this link.

    On a high level, you can refer to the below architecture diagram of Symmetrix family storage provisioning (applicable to PowerMax as well). This will give you heads up on different definitions and object names used in DellEMC PowerMax.

    DellEMC Symmetrix Family – Storage Provisioning

    Assuming now we have an understanding of PowerMax definitions, let’s get started on creating Ansible playbook.

    Note that the default behavior of Ansible is to use SSH for executing tasks on managed hosts, for which we make hosts file entry. Below is the example of specifying host in the hosts file.

    - hosts: webserver

    But DellEMC PowerMax Ansible module wraps the RestAPI commands of an array, hence hosts entry isn’t needed. When creating Ansible playbooks for DellEMC PowerMax we’ll need to create the playbook like the below example.

    - hosts: localhost
  connection: local
  gather_facts: no

    Now let’s talk about how to create playbook. Below is the simple ansible playbook to create storage group. 

    ---
- hosts: localhost
  connection: local
  gather_facts: no

  tasks:
    - name: Create Storage Group using Ansible
      dellemc_powermax_storagegroup:
        serial_no: "000111111333"
        unispherehost: "1.1.1.1"
        universion: "90"
        verifycert: false
        user: "pm_username"
        password: "my_password"
        sg_name: "mySG"
        state: 'present'

    Let’s understand tasks parameters used in above sample playbook

    • dellemc_powermax_storagegroup – ansible module used for creating storage group
    • serial_no – Serial number of PowerMax array. Replace this with your array serial
    • unispherehost – IP or hostname of PowerMax Unisphere management. Replace this with your array’s IP/hostname
    • universion – Unisphere version
    • verifiycert – Unisphere might be running on self signed certificate. You can ask ansible to ignore the certificate verification (value = false).
    • user – Unisphere username
    • password – Password for supplied username
    • sg_name – Name of the Storage Group you want to create

    Last 2 lines is where all the magic happens. Here we are asking ansible to create new SG named “mySG”.

    Note that though we have supplied credentials and PowerMax array details in the same playbook, it’s not mandatory. You can always move the variables in the separate file and using Ansible vault to make playbooks reusable (more on this in another blog).

    I hope this helps everyone to get started with automation of DellEMC PowerMax Day 1/2 tasks using Ansible. We will discuss on more sample playbooks in next blog post.

  • Ansible with DellEMC Storage: Part 3 – Installing DellEMC PowerMax Ansible Module

    Ansible with DellEMC Storage: Part 3 – Installing DellEMC PowerMax Ansible Module

    This blog is the continuation of Ansible with DellEMC storage multi-part blog. 

    In Part 1 of this series, we discussed getting started with the installation of dependencies for the Ansible and DellEMC Ansible module, followed by Ansible installation.

    In Part 2 we discussed the high-level basics of Ansible to get you started quickly.

    The purpose of earlier blogs was to get you to familiarize yourself with Ansible. In this blog, we will talk about DellEMC PowerMax Ansible module.

    First let’s get our management server ready. Make sure following pre-requisites are in place

    • PowerMax is running with Unisphere 9.0
    • Red Hat Enterprise Linux 7.5 (or equivalent). CentOS in my case
    • Ansible is installed (min version 2.6)
    • Python 2.7.12 or higher is installed
    • Python library for Unisphere (PyU4V) 3.0.0.14 is installed

    Ansible relies on Python and the Ansible for PowerMax modules rely on the PyU4V Python library. Check this link for more details on the latest PyU4V module.

    Make sure that Python and “pip” are installed. pip is a Python package manager. Install “pip” if required and then use it to install PyU4V.

    Below commands will get pip and PyU4V installed.

    # python -V
# pip -V
# yum install python-pip
# pip install PyU4V

    Once the system is ready with required packages next step is to get the PowerMax module from GitHub. To get the modules run below commands.

    # git clone https://github.com/dell/ansible-powermax
# cd dellemc_ansible
# ls

    This folder (dellemc_ansible) contains multiple documents including “Product Guide” and “Release Notes” for the downloaded version.

    We also need to copy a few files from downloaded modules to Ansible directories. Follow below process to complete the copy operation

    # cp utils/* /usr/lib/python2.7/site-packages/ansible/module_utils/
# mkdir /usr/lib/python2.7/site-packages/ansible/modules/storage/dellemc/
# cd /powermax/library
# ls
# cp * /usr/lib/python2.7/site-packages/ansible/modules/storage/dellemc/

    You’ll get an error in case of dellemc directory already exists, which you can ignore.

    At this point, we are ready with an Ansible server with DellEMC PowerMax modules installed.

    There are multiple files in the downloaded directory, each for different management tasks of DellEMC PowerMax (SRP, Volumes, Masking, etc.). We’ll discuss each module in the next blog post in this series.

  • Ansible with DellEMC Storage: Part 2 – Understanding Ansible

    Ansible with DellEMC Storage: Part 2 – Understanding Ansible

    This blog is the continuation of Ansible with DellEMC storage series. Earlier we discussed about getting started with installation of dependencies for Ansible and DellEMC Ansible module, followed by Ansible installation.

    In this blog let’s talk more around Ansible architecture and it’s concepts. So let’ get started.

    Similar to any other platform or software Ansible also has it’s own concepts which you should understand. This will help you get better hands-on with Ansible.

    Below diagram is the high level depiction of the Ansible concepts.

    Ansible Concepts

    On high level there are two types of nodes

    Managed Nodes (Right side of the diagram) – Managed nodes are the devices or software you’ll manage using Ansible. Note that managed nodes don’t need Ansible installed.

    Control/Master Node (Left side of the diagram) – This the machine Ansible is installed. On which you’ll login to run Ansible commands.

    Master node as multiple components which work together. Below are the high level details

    1. Inventory – This is the list of managed nodes which Ansible will talk to. Ansible always refers to node details from inventory file for executing any tasks. Inventory file support grouping, nesting, etc. which makes it easier for management and administration
    2. Modules – Each module defines certain Ansible function. You can execute modules using defining multiple tasks as part of playbooks
    3. Ansible Config – Consider this file as database of Ansible environment variables. Variables set in Ansible config supersedes any other setting configured in Ansible. Usually default configurations in this file are enough for many environments but there will be situations where you need to edit this file (/etc/ansible/ansible.cfg).
    4. Playbooks – Consider playbooks as list of many tasks which Ansible will execute in the sequence. Playbooks are written in YAML (.yml) and hence they are very easy to create and manage without the extensive knowledge of the coding.

    To simplify the playbook understanding just remember that

    • Playbooks contains Plays
      • Plays contains Tasks
        • Tasks call Modules

    Below is the example of Ansible Playbook

    sample Ansible playbook

    There are more concepts when it comes to Ansible (like Tower, Vault, Variables, etc.) but in my personal experience this is the good starting point.

    If you find this information stimulating enough and you want to read further then I would highly recommend that you start from here.

    I hope these bite sized blogs are helping you pickup Ansible faster. More to come 🙂

  • Ansible with DellEMC Storage: Part 1 – Installing Ansible

    Ansible with DellEMC Storage: Part 1 – Installing Ansible

    There are many blogs which cover what is Ansible and why we should care. But this multi-part blog series will cover how DellEMC and Ansible can help you automate many storage tasks.

    Ansible is being used in many organizations nowadays to manage a vast range of infrastructure, ranging from traditional configuration management to cloud resources in public clouds to physical infrastructure such as network and storage devices. There are multiple reasons why you might want to use Ansible, including – but not limited to – below examples.

    • You’re trying to have efficient DevOps environment
    • Automate Day 1/2 tasks
    • Need centralized configuration management

    Getting Started with Ansible

    Even if you’ve not installed Ansible before, it’s very easy to get started. There are many different ways to install Ansible and many dependencies will be needed based on your environment and systems you’ll be managing.

    Once your Linux machine is up and running (CentOS in my case) you can follow next steps

    Apart from Ansible itself there will be many dependencies which needs to be installed. In the case of DellEMC PowerMax storage we will need

    Note that Ansible relies on Python and the Ansible for PowerMax modules relies on a the PyU4V Python library

    So let’s get started

    Check the installed Python version by running below command and make sure it’s supported version

    # python -V

    For installing PIP package on CentOS you will need to install EPEL repository, which can be done by running below command

    # sudo yum install epel-release -y

    Once EPEL is installed you can run below command to install PIP. Also check version once installed

    # sudo yum install python-pip -y
# pip -V

    As mentioned earlier DellEMC PowerMax Ansible integration relies on a the PyU4V Python library Run below command to install PyU4V

    # pip install PyU4V

    Finally run below command to install Ansible

    # sudo yum install ansible

    At this point you have successfully installed Ansible and ready for next parts.

  • What is Container Storage Integration (CSI) and Why now?

    What is Container Storage Integration (CSI) and Why now?

    Containers are everywhere and they are here to stay. They are great level-playing ground to break the infrastructure dependency and allow developers to release their code to any environment.

    Containers also help customers to operate at greater scales with ability to quickly scaling up and down, patching with disruptions, withstand infrastructure component failures, moving easily from on-premises to public clouds, etc.

    As per the survey from sysdig lifespan of containers and container images is also very short.

    At this stage of the popularity of containers there are two thought processes in the container fan club – Persistent or Non-Persistent Containers

    If you explore docker hub top downloads you’ll notice that 7/10 top downloads require data persistence (snippet below)

    Let’s understand persistent containers in more details.

    Prior to Container Storage Integration CSI, Kubernetes provided in-tree (ie as part of the core code) plugins to support volumes but that posed a problem in that storage vendors had to align to the Kubernetes release process to fix a bug or to release new features among other problems. This also means every storage vendor had their own process to present volumes to Kubernetes.

    This heterogeneous non-standard integrations were one of the biggest reasons why CSI was created. CSI was developed as a standard for exposing block and file storage storage systems to containerized workloads on Container Orchestration Systems (COs) like Kubernetes. With the adoption of the Container Storage Interface (CSI), the Kubernetes volume layer becomes truly extensible. Using CSI, third-party storage providers like DellEMC can write and deploy plugins exposing new storage systems in Kubernetes without ever having to touch the core Kubernetes code. This gives Kubernetes users more options for storage and makes the system more secure and reliable. Also this approach makes sure that every vendor has standard way of interacting with Kubernetes.

    With CSI Kubernetes supports Persistent Volumes (PV). PVs life-cycle independent of any Kubernetes POD. Kubernetes supports 2 ways to provision PVs

    • Static – Admin Pre-provisions / creates a number of PVs
    Static PV provisioning
    • Dynamic – Cluster “automatically” provisions a volume
    Dynamic PV provisioning

    No matter which is the method of PV provisioning it can support varying properties such as performance, QOS, backup policies, etc. These properties are defined by StorageClass

    There are 3 access modes which are supported on PV. Storage volume cannot be mounted simultaneously in more than one access mode.

    1. ReadWriteOnce (RWO) – Volume can be mounted as ready-write by a single node
    2. ReadOnlyMany (ROX) – Volume can be mounted read-only by many nodes
    3. ReadWriteMany (RWX) – Volume can be mounted as read-write by many nodes

    Below is the summary of persistence

    DellEMC CSI Support

    DellEMC understands that that Enterprise applications require persistent storage. As of now (Nov 2019) DellEMC supports CSI plugins for below storage arrays

    Below are few documents around DellEMC CSI integration

    More blogs on CSI coming up 🙂

  • Ansible Master – Enabling SSH Key Based Authentication

    Ansible Master – Enabling SSH Key Based Authentication

    This section seems pretty straight-forward but is the must for all the Ansible deployments.

    Follow below steps to get through the password maze in Ansible environments

    Firstly we will need to generate the SSH authentication keys. This needs to be done on the server from which you want to login to other hosts. In my case it’s Ansible master server.

    Generate your key – Run the ssh-keygen command (as below). By default system will create and store the SSH key into /root/.ssh/id_rsa, which you can change. Passphrase is optional and you can leave it blank.

    Note that if you already have generated the SSH key you have option to overwrite the same, but make sure that earlier key is not used anywhere for authentication. Below example shows option to replace existing SSH keys

    [root@ansible-master ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
/root/.ssh/id_rsa already exists.
Overwrite (y/n)? y
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:D52Rvc2F7JMlbikpj7G96Ys3bSLRUz4tNmsfNP4E2Vg root@ansible-master
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|           o . . |
|          o . + E|
|         . o B.@ |
|        S =.+o&+.|
|         o.BooOoo|
|          +.o+ B.|
|          ..+o=.o|
|          .+=* .o|
+----[SHA256]-----+

    If you want to use existing keys then you can simply read the existing key which is saved in the file. Below is the example of the reading existing public key

    [root@ansible-master ~]# cat /root/.ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDDoN5+wFiV3Nold4Y7KDGkvIGBqulvdDxDm3qPj7SGsHsnEZKKxbQtO2QJNDJW2tXhLLDxY7vnyQ3xiL0bXbUTkeHHANFY7yZnMH4LH1k51yAkgDdVzKYUdvVJ81qRmYaJUJnLCsKvZMFmg7/KzecuA1QU8WVDLCH02HiRsmqVPaykcR2EOKCgX7i92Q/khZycR66GvoKcVwU9LuDLlADQt9GTaFDFiXPITNayvXkWvL7bwe9arqMCJzmEpvveglJI+vLvh5793yxrszTScTuMpjvpp4Nz5Tk0NSvQqo73yiHAsFF6M7l2hnVskyj3cAOL1dzxmopC/E1qd3DrWSOX root@ansible-master

    Once you have generated the SSH key next step is to add the key into target system.

    For copying the SSH keys into target system simply follow below process.

    [root@ansible-master ~]# ssh-copy-id root@192.168.1.101
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.1.101 (192.168.1.101)' can't be established.
ECDSA key fingerprint is SHA256:qnOPcE09JqKALwLLaL+SqNMy2oubvhF/EevGCcK9S9A.
ECDSA key fingerprint is MD5:4d:65:b7:e0:e8:09:41:a8:f9:4c:2d:b6:47:55:b2:09.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.1.101's password:

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@192.168.1.101'"
and check to make sure that only the key(s) you wanted were added.

    You’ll notice in the command output that this process has added the key into the target system. Note that 192.168.1.101 in above example is target system in which I wanted Ansible master to login without username and password.

    Once the SSH keys are added into the target system now you can try SSH into the target system and it won’t ask for password anymore.

    [root@ansible-master ~]# ssh root@192.168.1.101
Last login: Tue Nov 26 09:01:16 2019 from gateway
[root@target-system ~]#

    Hope this saves time for many of us.