Category Archives: VMware Cloud on AWS

The Importance of VMware Cloud on AWS Storage Policies

This post talks about the importance of using Storage Policies with VMware Cloud on AWS to ensure the most efficient consumption of the available vSAN capacity. As a VMware Cloud on AWS customer this is something we initially overlooked, allowing the default policy to remain in place for a period of time. The end result was burning through the storage capacity quicker than expected.

It is important to note here that VMware recommend keeping 30% free/slack space to keep vSAN operational. While compute features such as Elastic DRS can be disabled, in order to keep the integrity of vSAN and associated Service Level Agreements (SLAs) clusters will automatically scale out in the event a storage threshold is hit. Customers should monitor their datastore and capacity usage to avoid unexpected charges of additional hosts being added.

First of all this great blog by Glenn Sizemore identifies How Storage Policies influence usable capacity in VMware Cloud on AWS. When planning your capacity you should also review the Storage Capacity and Data Redundancy section of the VMware Cloud documentation.

SDDC Storage Options

When deploying the SDDC, the customer has the option of deploying a Stretched Cluster. Although a single cluster provides High Availability (HA) between hosts , it is restricted to a single Availability Zone (AZ) within a region. This is backed by a 99.9% availability guarantee. A Stretched Cluster is spread across 2 Availability Zones within a region, with a third acting as witness. This is backed by a 99.99% availability guarantee. At the time of writing it is not possible to mix cluster types within an SDDC.

There are currently 3 methods of consuming storage with VMware Cloud on AWS:

  • Direct Attached NVMe
    • i3.metal instances provide fixed capacity in the form of NVMe SSDs with high IOPS. This storage type is suitable for most use cases including workloads with high transaction rates such as databases, high-speed analytics, and virtual desktops. The i3.metal instances offer 36 CPU, 512GiB RAM, and 10TiB direct-attached NVMe high IOPS vSAN storage.
  • Elastic vSAN
    • r5.metal instances provide dynamic capacity using Amazon Elastic Block Storage (EBS), suitable for high or changing capacity needs and lower transaction rates; data warehousing, batch processing, disaster recovery, etc. The r5.metal instances offer 48 CPU, 768GiB RAM, and 15-35TiB AWS Elastic Block Storage (EBS) providing cloud native Elastic vSAN made up of General Purpose SSDs (GP2).
  • External Storage
    • Finally, storage can be scaled with external storage from a Managed Service Provider (MSP) like Faction, who are closely followed by others such as Rackspace and Netapp. Currently the VMware Cloud public roadmap also lists ‘External datastore and guest OS storage access for both DX and ENI connected 3rd party storage’ as developing, although this may change.

Additional pointers:

  • There are additional instance types in development with further storage options.
  • Management servers are stored on the first cluster provisioned (Cluster0). The datastores are administrative delegation points, the management datastore is managed by VMware and the workload datastore is for the customer to consume.
  • Data-at-rest encryption is provided by vSAN using the AWS Key Management Service (KMS). VMware Operations own the KMS relationship and Customer Master Key (CMK). The service is FIPS 140-2 compliant with full auditing, although this is sufficient for most use cases there currently isn’t a supported use case for customers who must own the KMS relationship themselves.

Storage Policies

With VMware Cloud on AWS the customer sets the desired end state and VMware manage the configuration. This means the technical details are not that in depth; the customer tells VMware how many hosts they want in the cluster, and the policies to apply. Storage Policies can be applied to one to many Virtual Machines (VMs), Virtual Machine Disks (VMDKs), or VMDKs for container persistent volumes. In other words they are applied at object level, rather than for an entire datastore.

Storage Policies can be used to define things like disk stripes, IOPS limits, space or cache reservation, and availability. In this particular use case we are interested in weighing up the availability options with space efficiency:

  • No data redundancy: requires 1 host, 100GB of data used writes 100GB of data in the back end.
  • Tolerate 1 host failure: RAID1, requires 3 hosts, 100 GB of data used writes 200GB of data in the back end. In this scenario vSAN adds a second copy of the data, and a witness copy to prevent split brain scenario. We can lose any 1 of the 3 hosts and the object stays available. Although the storage consumption has doubled, reads are load balanced to accelerate performance, writes still need to be synchronously committed.
  • Tolerate 2 host failures: RAID1, requires 5 hosts, 100GB of data used writes 300GB of data in the back end. You get the picture, this means that the storage consumption could get quite high.
  • Erasure Coding: by implementing an Erasure Coding policy, instead of storing an entire copy of the data it instead gets broken up into multiple data segments. We can lose any 1 chunk of that data and not suffer data loss, however there is additional I/O associated with managing the parity copy. Furthermore, in the event of a failure the data has to be rebuilt meaning potential for a compute and I/O overhead during this time. Despite this, the policy proves good for space efficiency where workloads may not be hugely performance intensive.

Additional pointers:

  • In a Stretched Cluster there is a feature called read locality; keeping reads within a same AZ. Remember though that writes must be synchronous across both AZs.
  • Data transfer fees are $0.02/GB for cross-AZ traffic, tools like Live Optics can be used to predict application read and writes.
  • Not all your workloads will need vSphere HA protection across AZs, for example developer workloads or workloads where failover is provided in the application stack such as SQL Always On.

Storage_Policies

Bridging the Gap Between NHS and Public Cloud with VMware Cloud on AWS

Following on from How VMware is Accelerating NHS Cloud Adoption, this post dives into more detail around how the UK National Health Service (NHS) can use VMware Cloud on AWS to bridge the gap between existing investments and Public Cloud.

Part 1: How VMware is Accelerating NHS Cloud Adoption

Part 2: Bridging the Gap Between NHS and Public Cloud with VMware Cloud on AWS

Example NHS VMware Cloud on AWS Use Cases

Modern Applications: The VMware strategy of late has seen a significant shift towards cloud agnostic software and the integration of cloud-native application development. VMware Cloud on AWS makes use of the full VMware Software-Defined Data Centre (SDDC) stack; enhancing security of NHS applications with micro-segmentation, and future-proofing application development with Project Pacific (Understand VMware Tanzu, Pacific, and Kubernetes for VMware Administrators).

Data Centre Expansion or Disaster Recovery: VMware Cloud on AWS can reduce NHS data centre footprint on-premise, by expanding new capacity into VMware Cloud on AWS (Deploy and Configure VMware Cloud on AWS), or through the addition of a Disaster Recovery (DR) site accompanied with VMware Site Recovery Manager (SRM). Legacy Data Centre Evacuation: VMware Cloud on AWS can replace legacy data centres by facilitating the migration of VMware Virtual Machines (VMs) from end of life hardware to VMware Cloud on AWS (Migrate VMware Virtual Machines to VMware Cloud on AWS). In some cases, dependant on internal finance policies, NHS organisations may be able to capitalise the cost of reserved instances (dedicated physical hosts for 1 or 3 years) in VMware Cloud on AWS using recently introduced IFRS 16 Leases. For more information review the Capitalising Your Cloud Booklet.

Hosting NHS Patient Data: There are a number of security principles which should be implemented to host patient or sensitive data, further information is available on the NHS Digital website. Important detail on the shared security model of Public Cloud, and further VMware and AWS specific links, can be found in the How VMware is Accelerating NHS Cloud Adoption article. A summary excerpt is below:

“In January 2018 NHS Digital released guidance for NHS and social care data: off-shoring and the use of public cloud services, along with a toolset for identifying and assessing data risk classification. The NHS and social care data: off-shoring and the use of public cloud services guidance paper published by NHS Digital states; ‘NHS and social care organisations can safely put health and care data, including non-personal data and confidential patient information, into the public cloud’. The NHS and social care providers may use cloud computing services for NHS data, providing it is hosted in the UK, or European Economic Area (EEA), or in the US where covered by Privacy Shield.”

“Each individual data controller organisation is responsible for implementing and reviewing their own processes around data risk classifications, however to assist NHS Digital have provided a consistent health and social care data risk model. For organisations that do not yet have cloud governance in place NHS Digital have also provided guidance on the health and social care cloud risk framework.

Cloud services introduce a shared security model. NHS organisations can be compliant by implementing a cloud risk framework and proportionate controls outlined by NHS Digital; summarised in the health and social care cloud security one page overview. Security considerations for different data classifications are detailed in the health and social care cloud security – good practice guide.”

Moving to Internet First: As well as the Cloud First strategy outlined in the article referenced above, the UK Government also seeks to make public sector applications, systems, and services accessible over the Internet, with the Internet First strategy. VMware Cloud on AWS can utilise existing on-premise Health and Social Care Network (HSCN) connections, but can also offer the ideal opportunity to move services to Internet facing. This can be supported with the correct network design, and through making use of native AWS services. There is more information below on how VMware Cloud on AWS compliements Internet First, and further reading on the NHS Digital Internet First policy can be found here.

“Health and care services now have an Internet First policy that states new digital services should operate over the internet. Existing services should also be updated to do the same at the earliest opportunity and ideally by March 2021.”

Example Native AWS Service Integrations

In the example architecture below a Stretched Cluster has been deployed across 2 AWS Availability Zones in the London region (eu-west-2), providing VMware Virtual Machine (VM) availability across sites and fault domains. Amazon Direct Connect provides a private link from on-premise networks and should be deployed with resilience, a standby Virtual Private Network (VPN) encrypted connection can also be used. To see these features in action review Watch VMware vSphere HA Recover Virtual Machines Across AWS Availability Zones, and Watch a Failover from Direct Connect to Backup VPN for VMware Cloud on AWS. Optional access to the Health and Social Care Network (HSCN) is provided by the existing on-premise HSCN connection.

Example_VMC

Focusing on the VMware Cloud on AWS connectivity into native AWS services from the example architecture we can note the following:

  • Connectivity to native AWS services is provided using Elastic Network Interfaces (ENI), a 25Gbps link into Amazon’s backbone network.
  • Traffic traversing the ENI (ingress and egress) is not chargeable. Any deployed services in AWS are chargeable as normal against the connected AWS account.
  • Using a Virtual Private Cloud (VPC) endpoint NHS organisations can make use of Regional Amazon services such as Simple Storage Services (S3), which offers a tiered approach to object storage and pricing, or Glacier for data archive.
  • Using the Virtual Private Cloud (VPC) router NHS organisations can make use of services such as Elastic Compute Cloud (EC2), or managed databases with Relational Database Service (RDS).

An example scenario could be an on-premise application with a large database which does not have the development resource or funding to refactor for native Public Cloud. It could also be that refactoring this application doesn’t offer any additional business benefit or functionality. In this case the database could be migrated to RDS, and the front end web / application servers could be migrated ‘as is’ to run on VMware Cloud on AWS. Using the 25Gbps ENI would, in most cases, remove any latency concerns between the application and the database.

It is important to remember that it isn’t only the consumption of traditional infrastructure services that is on offer. Opening up existing workloads to native AWS services drives innovation and modernisation of applications. One example is Amazon’s Artificial Intelligence (AI) powered voice assistant Alexa, which now gives health advice using information from the NHS website. In addition to AI and Machine Learning, AWS has a portfolio of data lakes and analytics services, enabling cost effective methods for NHS organisations to collect, store, analyse, and share data.

Example_Native

In the case of Internet First, VMware Cloud on AWS in conjunction with native AWS can help scale and consolidate publicly accessible applications, as documented in VMware Cloud on AWS Reference Architectures. In one such example, the following AWS services are used to facilitate public services hosted in VMware Cloud on AWS:

  • Amazon Route 53 is a highly available and scalable cloud Domain Name System (DNS) web service for name resolution.
  • Elastic Load Balancing automatically distributes incoming application traffic across multiple targets. The Application Load Balancer is best suited for load balancing of HTTP and HTTPS traffic operating at the individual request level (Layer 7).
  • AWS Certificate Manager is a service that lets you easily provision, manage, and deploy public and private SSL/TLS certificates for use with AWS services and your internal connected resources.

Additional optional services for performance and security:

  • Amazon CloudFront is a fast Content Delivery Network (CDN) service that securely delivers data, videos, applications, and APIs to customers with low latency, high transfer speeds.
  • AWS Shield is a managed Distributed Denial of Service (DDoS) protection service that safeguards applications running on AWS.
  • AWS WAF is a Web Application Firewall that helps protect your web applications from common web exploits that could affect application availability or compromise security.
  • AWS CloudTrail is a service that enables governance, compliance, operational auditing, and risk auditing of your AWS account.

VMC_ELB

Further Reading: How to Deploy and Configure VMware Cloud on AWS (Part 1), How to Migrate VMware Virtual Machines to VMware Cloud on AWS (Part 2).

VMware Cloud on AWS FAQs | Resources | Documentation | Factbook | Evaluation Guide | On-Boarding Handbook | Operating Principles

How to Migrate VMware Virtual Machines to VMware Cloud on AWS

This post pulls together the workload migration planning and lessons learned notes made during a real life customer use case of evacuation an on-premise date centre to VMware Cloud (VMC) on AWS (Amazon Web Services). The content is a work in progress and intended as a generic list of considerations and useful links for both VMware and AWS, it is not a comprehensive guide. Cloud, more-so than traditional infrastructure, is constantly changing. Features are implemented regularly and transparently so always validate against official documentation. This post was last updated on September 16th 2019.

Part 1: SDDC Deployment

Part 2: Migration Planning & Lessons Learned

1. Virtual Machine Migrations

The following points should help with the planning of Virtual Machine (VM) workload migrations to VMware Cloud on AWS. An assumption is made that the Software Defined Data Centre (SDDC) is stood up and operational with monitoring, backups, Anti-Virus, etc. in place. Review Part 1: SDDC Deployment for more information. I found the SDDC deployment and getting the environment available was the easy part. Internal processes and complexity of the existing environment are going to determine how quickly you can migrate workloads to the SDDC.

We started by exporting a list of Virtual Machines from each vCenter, from that we identified the service it was running and the service owner or business owner. The biggest surprise here was the amount of servers deployed by, or for, people who had left the organisation. These servers were still being hosted, maintained, patched, but no longer needed. We were able to decommission more workloads than expected due to years of VM sprawl. Whilst VMware Cloud on AWS isn’t directly responsible for this the project forced us to evaluate each server we hosted. For remaining workloads we put together a migration flow which identified the following criteria:

  • CPU, RAM, storage requirements: identified a baseline to automatically accept and then anything above our baseline would require a manual check.
  • Network dependencies: is there a large amount of data in transit, is IP retention required, is the VLAN stretched using Hybrid Cloud Extension (HCX), load balancer requirements.
  • Data flows: used vRealize Network Insight to identify potential egress costs and additional service dependencies.
  • Additional application or organisation specific considerations: e.g. data classification, tagging / charge-back model, backups, security, monitoring, DNS, authentication, licensing or support.
  • Service Management considerations: is the service platinum/gold/silver/bronze or unclassified, do the platform Service Level Agreements (SLAs) fulfil the existing SLAs in place for each service, is the proposed migration type (i.e. amount of downtime) taking this into consideration. Involving Service Management right from the start was useful as they were able to advise on internal processes for Service Acceptance and Business Continuity.
  • Service Owner considerations: if the technical criteria above is met then the next step was to meet with service owners and get their buy-in for the migration. We migrated internal services we owned first, and then used that as a success story to onboard other services. This process involved meeting with various departments, presenting the solution and the benefits over their existing hosting, in our case DR and performance improvements, and migrating dev or test workloads first to build confidence.
  • Migration passport: one of our Senior Engineers came up with this concept as a one-pager for each service that was migrated, it consisted of migration details (change ID, date, status), migration scope (server names, locations, and notes), firewall rules, vRNI outputs, and other information such as associated documentation.

Each environment is different so these are provided as example considerations only. Use resources such as those outlined below, and , to develop your own migration strategy.

Workload_Mobility

2. Network Design

  • Research the differences and limitations around the different VMware on AWS connection types, especially under 1Gbps – Configuring AWS Direct Connect with VMware Cloud on AWS
    • Make sure you understand the terminology around a Virtual Interface (VIF) and the difference between a Standard VIF, Hosted VIF, and Hosted Connection: What’s the difference between a hosted virtual interface (VIF) and a hosted connection? It is important to consider that VMware Cloud on AWS requires a dedicated Virtual Interface (VIF) – or a pair of VIFs for resilience. If you have a standard 1Gbps or 10Gbps connection direct from Amazon then you can create and allocate VIFs for this purpose. If you are using a hosted connection from an Amazon Partner Network (APN) for sub-1G connectivity then you may need to procure additional VIFs, or a dedicated Direct Connect with the ability to have multiple VIFs on a single circuit. This is a discussion you should have with your APN partner.

  • The Virtual Private Cloud (VPC) provided by the shadow AWS account cannot be used as a transit VPC. In other words if you want to connect to private IP addressing of native AWS services you cannot hop via VMware Cloud. In this instance a Transit Gateway can be used.
  • At the time of writing a VPN attachment must be created to connect the SDDC to a Transit Gateway, if Direct Connect is in use then the minimum requirement is 1Gbps.
  • If there is a requirement to connect multiple existing AWS VPCs, or multiple SDDCs, with on-premise networks then definitely check out VMware Cloud on AWS with Transit Gateway Demo.
  • If a backup VPN is in use then you may be able to reduce failover time using Bidirectional Forwarding Detection (BFD) which is automatically enabled by AWS, in our case it was not supported by our third party provider.
  • Use vRealize Network Insight to get an idea of dependencies and data flows that you can use to plan firewall rules and estimate egress or cross-AZ charges. In general my experience with these charges is that they have been minimal, this depends entirely on your own environment but should be considered when calculating overall VMware on AWS pricing.
  • If you want to update your default route see How to Set the Default Route in VMware Cloud on AWS: Part 1 & Part 2.
  • VMware Cloud on AWS: NSX Networking and Security eBook

3. Load Balancing & Security

  • With the acquisition of Avi Networks we can expect Avi Networks services as a paid add-on for VMware Cloud: VMware Cloud on AWS: NSX and Avi Networks Load Balancing and Security.
  • Third party load balancers such as virtual F5 can be deployed in virtual appliance format. If you are planning on using AWS Elastic Load Balancer (ELB) on a private IP address accessible on-premise ensure you have a connectivity method as outlined above.
  • The NSX Distributed Firewall (DFW) feature is included in the price of VMware Cloud, the paid for message is removed from SDDC v1.8 onwards, this was announced at VMworld 2019.
  • Another VMworld 2019 announcement was the inclusion of syslog forwarding with the free version of VMware Cloud Log Intelligence (SaaS offering for log analytics), although for troubleshooting NSX DFW logs you still need the paid for version.
  • If you are using HCX this product uses its own IPSec tunnel and therefore we could not get it working with the private IP address over a backup VPN. It was assumed that HCX would also not work with the private IP address via Transit Gateway either, due to the SDDC VPN requirement, and would need to be reconfigured to use the public IP address.
  • Another HCX migration consideration is that when you are stretching a network all traffic goes via the HCX Interconnects. This means you are encapsulating everything in port UDP 4500, and essentially bypassing your on-premise firewall rules while the network is stretched. It is important to double check all rules are correct before eventually moving the gateway to VMC.
  • Again if you are doing VMware HCX migrations, remember to remove stretched networks once complete. This involves shutting down the gateway on-premise, removing the L2 stretch, and changing the network in the SDDC to routed, for us the down time was around 30 seconds. The deployment of HCX in our environment, although covered by vSphere High Availability (HA), didn’t have resilience built in, therefore we decided to minimise the amount of time they were in use by planning a migration strategy around each subnet.
  • If you use NSX Service Deployments for Anti-Virus, i.e. Guest Introspection for agentless AV then you will need to deploy an agent on each VM, as this feature is still currently unavailable.

4. General

  • The Cloud Services Portal (CSP) can be integrated with enterprise federation, allowing you to control access using your organisational policies, hopefully therefore enforcing Multi-Factor Authentication (MFA) and removing access as part of a leavers process. Federation will only work with a tenant, it will not work with a master organisation.
  • It is not possible at the time of writing to easily transfer an SDDC deployed in the root/master organisation into a tenant. The process currently is a redeploy and migrate.
  • Druva offer a product that will backup Virtual Machines from VMware Public Cloud direct into an S3 bucket they manage, for a greenfield deployment if you are not transferring any existing licenses this could be a good option as you only pay for the capacity you use. Having a backup environment setup in AWS has many benefits but also adds a management overhead and the consideration of replicating between Availability Zones.
  • In general internal support was good once teams were educated on the platform and the slightly different operating model we were implementing. In terms of external support we have not encountered any compatibility issues yet, there was one application vendor with a published KB article stating they support running the application on VMware Cloud on AWS,  then back tracked and said they wouldn’t support it as vSphere was a version not yet GA (6.8 at the time of writing).