Tech Tips, Tricks & Trivia

This Week I Learned - *  On-premises servers running Windows Server 2008 or 2008 R2 can be migrated to Azure using Azure Site Recovery *  Azure Site Recovery has been tested and integrated with SAP applications. *  Currently it is not possible to protect a virtual machine that has a Docker disk  using ASR * You can migrate a Recovery Services vault (an Azure Resource Manager resource to manage your backup and disaster recovery needs natively in the cloud) between subscriptions and resource groups with a few steps, in minimal downtime and without any data-loss of old backups . *  Replatforming involves upgrading an application from its existing platform and adhering to the minimum possible Twelve factors to get it to run on the cloud, while preserving existing functionality. *  The Azure Site Recovery SLA guarantees a two-hour Recovery Time Objective for Azure-to-Azure Failover.   *  From a design perspective it is nearly impos...

Since October 2017, I've been tracking the Regions of the popular public cloud providers - AWS, Azure & GCP, on a custom Google Map . The map lists all the locations (though not exactly & only those that are officially revealed) while pictorially consolidating information provided through official documentation. The highlight of the custom map is the Search feature. For example, if the target audience for an app to be deployed to public cloud is in San Juan, the Search feature will let you see (after a little zooming) which are the AWS, Azure, GCP regions closest to it that can be potentially used. Here are the April 2019 Stats: * AWS - 20 Regions, 61 Availability Zones, 5 Regions & 15 AZs upcoming * Azure - 44 Regions, 10 Availability Zones, 10 Regions upcoming * GCP - 20 Regions, 61 Zones, 3 Regions upcoming Zoom in & out of the map to view details as required

This Week I Learned - *  ExpressRoute Direct provides direct connectivity to the Azure global backbone at 100 Gbps. This enables customers who have scenarios such as massive data ingestion to storage, physical isolation, dedicated capacity, and burst capacity to use Microsoft’s global backbone to access Azure regions at tremendous scale. *  Microsoft built ASR internally, and then integrated the InMage technology it acquired in 2014 to now provide DR for VMware, Hyper-V and physical workloads. * DNS is one of the most efficient mechanisms to divert network traffic because DNS is often global and external to the data center and is insulated from any regional or availability zone (AZ) level failures. One can use a DNS-based failover mechanism and in Azure, two DNS services can accomplish the same in some fashion - Azure DNS (authoritative DNS) and Azure Traffic Manager (DNS-based smart traffic routing). DNS is one of the most efficient mechanisms to divert network...

This Week I Learned - *  Both Azure SQL Database & Azure SQL Database Managed Instance have T-SQL differences when compared with SQL Server *  For better HA ...deploy the application in more than one region, and use Azure Traffic Manager to fail over if the application fails in one region. For a multi-region deployment, the composite SLA is calculated as follows. Let N be the composite SLA for the application deployed in one region, and R be the number of regions where the application is deployed. The expected chance that the application will fail in all regions at the same time is ((1 − N) ^ R). For example, if the single-region SLA is 99.95%, The combined SLA for two regions = (1 − (1 − 0.9995) ^ 2) = 99.999975% The combined SLA for four regions = (1 − (1 − 0.9995) ^ 4) = 99.999999% You must also factor in the SLA for Traffic Manager. At the time of this writing, the SLA for Traffic Manager SLA is 99.99%. Also, failing over is not instantaneous in active-passive c...

This Week I Learned - *  To use ExpressRoute for Site Recovery replication, you can utilize public peering (deprecated for new creations) or Microsoft peering. Microsoft peering is the recommended routing domain for replication. *  ASR uses a replication agent and Microsoft releases regular updates to support newer operating system versions as well as deliver bugfixes. Microsoft recommends maintaining the agent at no more than four versions behind the current release since the upgrade process becomes more involved and disruptive . * Steps to migrate a VMware virtual machine to Azure using Azure Site Recovery. Source: Kryptos *  Inside Azure Management  [PDF] is a free e-book written by Microsoft MVPs * There are two technical aspects towards setting up your disaster recovery architecture : - Using a deployment mechanism to replicate instances, data, and configurations between primary and standby environments. This type of disaster recovery can be done na...