Thursday, 22 September 2016

10 Things You Need to Know about Amazon EC2

Dedicated some time to understand Amazon Web Services by creating my Amazon Web Services account an spinning up some services.
Amazon Elastic Compute Cloud (EC2)

  • Is one of the most widely used web service which provides us resizable compute capacity and helps us to reduces the overall time which is required to obtain and boot new Amazon EC2 instance to minutes.
  • With Amazon EC2 we can increase/decrease the capacity in minutes with a complete control on our Amazon EC2 Instance by having root access.
  • Security is not a problem because we can make use of security groups and network access lists to control the incoming/outgoing connections of our instances.
  • When it comes to buying an EC2 Instance there are various options available out of which we can choose the one which meet our business needs, let's have a look on these options.
  • On Demand Instance let us pay for compute capacity on an hourly basis and we can increase or decrease compute capacity depending on the demands of our application and can considered as one good option when we are planning to run our application for the very first time on AWS.
  • Reserved Instances will gives us the assurance of the instances which will always be available for us in the availability zone for which we purchased it, including a discounted price as compared to the On demand Instance.

  • Spot Instances allows us to specify the maximum hourly price which we are willing to pay to run a particular instance type. Amazon EC2 sets a Spot Price for each instance type in each Availability Zone, which is the price all customers will pay to run a Spot instance for that given period. 

  • Dedicated Hosts as the name suggest is the EC2 Server with the overall capacity to be utilized by us and helping us reduce costs by using our existing server-bound software licenses, including Windows Server, SQL Server, and SUSE Linux Enterprise Server (subject to your license terms), and can also help you meet compliance requirements.
  • To maintain application availability we can make use of Auto Scaling which helps us to scale our Amazon EC2 capacity up or down automatically according to conditions defined by us.
  • Further to automatically distributes incoming application traffic across multiple Amazon EC2 instances in the cloud we can make use of Load Balancer Services provided as two different types of load balancer i.e Classic Load Balancer (which routes traffic based on application or network level information and is ideal for simple load balancing of traffic across multiple EC2 instances where high availability, automatic scaling, and robust security are required) and Application Load Balancer (Load Balancing service which operates at the application layer and allows us to define routing rules based on content across multiple services).

Monday, 19 September 2016

VCAP6-DCV Design Objective 2.1

We already had a detailed discussion about VCAP6 - DCV Design exam, where we discussed about the Path we need to follow and what are the objectives that we need to take care, If in case you missed it here is the link for your reference Kick Start Your Journey Towards VCAP6-DCV Design.

We have also seen VCAP6-DCV Design Objective 1.1, VCAP6-DCV Design Objective 1.2 and VCAP6-DCV Design Objective 1.3 in which we discussed about Business and Application Requirements and also talked about Risks,Constraints, Assumptions  here are the links for your reference VCAP6-DCV Design Objective 1.1, VCAP6-DCV Design Objective 1.2 , VCAP6-DCV Design Objective 1.3

Objective 2.1 : Mapping Business Requirements to a vSphere 6 Logical Design.

Skills and Abilities
  • Analyze requirements for functional and non-functional elements.
  • Build non-functional requirements into a specific logical design.
  • Translate stated business requirements into a logical design.
  • Incorporate the current state of a customer environment into a logical design.
How to Prepare

As part of the design process conceptual design is the first step when climbing the Design ladder which categories the assessment findings into requirements, contraints, assumptions and risk as discussed in our last post VCAP6-DCV Design Objective 1.3.

Sharing one  recent example from one of the project on which i worked , wherein we got requirements from customers (Marketing Business Firm) and they were looking to Virtualize their existing workload (Windows + Linux).
When doing the current state analysis and understanding the business requirements as part of the initial design phase we captured Business Requirements and I am highlighting few of them.
  • Virtualize and consolidate all existing physical servers running on the x86 platform
  • Architecture should meet the performance requirements calculated during the initial assessment phase.
  • Geographies Architecture should support both the Prod and Dev data centers.
  • The design should be scalable to support a virtual machine growth of 22 percent year over year growth.
  • The design should provide a centralized management console to manage both data centers.

It's definitely not the real diagram talking about the conceptual design for the same Marketing Business Firm, but it's more of near to real design diagram which talks about the conceptual design.

To maintain the integrity of their design i couldn't used the real picture but was able to manage and document almost everything included in conceptual design.

Now moving towards the original discussion of creating a Logical Design which typically includes the design decisions with proper justifications to arrange all the infrastructure level components (Management, Clusters, Networking, Storage, Virtual Machines) ensuring all the business requirements are satisfied as mentioned in conceptual design.

Design is an iterative phase within which we need to ensure that we are taking care of all the business and application requirements in conjunction with VMware and Industry Best practices.

It's not mandatory when working towards Logical Design all the design decisions should always come from business/application requirements it can also come from the non functional requirements for example Availability (How to ensure that services are available), Manageability (Is the Solution Flexible Enough), Recoverability (How well the solution meets RTO and RPO requirements).

Another example in Non Functional requirement which should be mentioned when working towards logical design (design decision) is Cost, every project has an associated cost if we are not able to lay the project in the defined cost we need to mention the same with proper justifications so as the required stakeholders can take necessary actions.

Let's have a look on Logical Design for the same Marketing Business Firm for which we have seen the Conceptual Design.
Design Justification
Design Implication
vCenter Server Platform

Windows Based vCenter
Marketing Business Firm mentioned they are comfortable with Windows based vCenter Appliance with their trained Windows Admin.
Frequent Patching is required for Windows Based vCenter Server
vCenter Server database

Embedded database is not large enough for complex deployments
Must be Prepared in Advance
Number of vCenter Server instances

Both for Prod and Dev Datacenters
Separate Licenses are required

Saturday, 17 September 2016

VMware VSAN is Up and Running Now @ Home Lab

In our last post we have seen overview about VMware vSAN if in case you might missed it here is the link for your reference. VMware VSAN Overview

Spent some time today to setup VMware VSAN in my Home Lab so thought of dedicating an article to understand the configuration of VSAN in your environment.

Those of you who already have their Home Lab setup and are planning to test the functionalities of VMware VSAN this article will help you and those who didn't have the Home lab setup need not to worry as we will be learning something New through this article.

Let's start with the prerequisites that we need to take care of before we set up the VMware VSAN cluster in our environment.

  • A minimum of three ESXi 6.0 hosts contributing local storage.
  • All ESXi hosts must be managed by vCenter Server 6.0 and configured as a Virtual SAN cluster member.
  • ESXi hosts in a VSAN cluster may not participate in any other cluster.
  • For hybrid configurations, each host must have a minimum of a single physical 1 GB Ethernet NIC available solely for Virtual SAN use.
  • For all flash configurations, each host must have a minimum of a single physical 10 GB Ethernet NIC available for Virtual SAN use.
  • VMKernel Port on each host dedicated for VSAN traffic.
In my home lab when i planned to configure VMWare VSAN I only had two ESXi host so quickly created the third ESXi host and added it to the cluster and enabled VSAN.

But it was not that straight forward as all of my ESXI's only had one disk which was initially being used when the ESXi host was installed so added more Disks to my ESXi so as these disks can be leveraged in VSAN Cluster.

VMware VSAN is all about leveraging underlying SSD's and HDD's presented on ESXi's host and creating VSAN shared datastore that's what we will also try to achieve from this post.

Still I was not able to proceed further and create Disk Groups ? What is a Disk Group !

To understand what is a disk group let's go back to Old Days when we took our first Virtualization lesson and learnt the definition of Virtualization "Abstracting the Underlying Hardware Resource and Pooling them together".

That's what we are doing abstracting the underlying HDD's and SSD's from each ESXi host and creating a main unit of storage known as DISK Groups.

When it comes to the creation of Disk Groups it can be created Automatically (Virtual SAN claims all available and usable disks and organizes them into default groups with one SSD and one or multiple HDDs) and Manually (Where we must specify hosts and disks on the hosts to be used for the Virtual SAN datastore.) 

For creation of Disk Groups each ESXi host must have a minimum of One SSD and One HDD in case of Hybrid Architecture (SSD+HDD) whereas in a DISK Group we can also have all the SSD's in ALL FLASH Architecture.

Minimum of one SSD is required but that wasn't the case in my Home Lab because all the extra Disks i added were added as HDD's, which was preventing the creation of Disk Groups.

It was time to play with ESXCLI commands and mark at least one disk as SSD to ensure the successful creation of a Disk Group.

Connected to all my hosts through putty and executed below ESXCLI commands.

esxcli storage nmp satp rule add -s VMW_SATP_LOCAL -d mpx.vmhba1:C0:T2:L0 -o enable_ssd

esxcli storage core claiming reclaim -d mpx.vmhba1:C1:T2:L0

esxcli storage core device list -d mix.vmhba1:C1:T2:L0

*Note: Installation/Configurations/Specifications methods used here has been Tested in My Home Lab Nested Environment.

Now that we have marked one of the Disks from ESXi host as SSD it time to check  if the Disk groups are now created.

I was able to see the disk groups and the VMware VSAN shared datastore created and the disks (SSD+HDD) been leveraged from all my ESXi host, the warning message on ESXi host is because of SSH service still running.

Was not able to wait and see my Virtual Machine spinning on newly created VMware VSAN shared datastore so storage vMotioned Virtual Machine (vMA) on VSAN Datastore.

To Summarize VMware VSAN is a cluster level feature which needs a minimum of 3 ESXi hosts talking to each other on same VSAN network and each host must have a minimum of one SSD and one HDD for creation of Disk Groups.

Will be dedicating more articles talking about the policies and features of VMware VSAN.