Sql Server High Availability & DR TechnologiesRockSolid SQL
There are many different disaster recovery and high availability options for SQL Server. Making decisions on the most effective DR & HA strategies can be complex, especially when you throw into the mix various SAN and network topologies.
This presentation is focused on the management and operational decisions that are made when planning DR and HA for production SQL Server environments. It is targeted towards Senior DBAs, CIO, IT Manager, database services managers.
Topics include:
Log Shipping
Database Mirroring
Always On High Availability groups
Replication
Clustering
Licensing
A basic overlook for some configurations when running SQL Server, SSRS and SSAS. Some configurations are also when the services are ran on the same stand alone server. There are also basic hardware considerations.
Sql Server High Availability & DR TechnologiesRockSolid SQL
There are many different disaster recovery and high availability options for SQL Server. Making decisions on the most effective DR & HA strategies can be complex, especially when you throw into the mix various SAN and network topologies.
This presentation is focused on the management and operational decisions that are made when planning DR and HA for production SQL Server environments. It is targeted towards Senior DBAs, CIO, IT Manager, database services managers.
Topics include:
Log Shipping
Database Mirroring
Always On High Availability groups
Replication
Clustering
Licensing
A basic overlook for some configurations when running SQL Server, SSRS and SSAS. Some configurations are also when the services are ran on the same stand alone server. There are also basic hardware considerations.
SQL Server AlwaysOn for Dummies SQLSaturday #202 EditionMark Broadbent
Welcome to Microsoft's world of the buzzword. Yes, they've done it again and created another ambiguous term that no one really understands. AlwaysOn is a powerful group of highly available technologies, and in this presentation, we will delve into their murky world & reveal the technology behind the buzz. Focusing specifically on the two key components of SQL Server 2012 AlwaysOn in Failover Clustered Instances and Availability Groups, we will investigate their pre-requisites, setup, administration, use & drawbacks. We will look at: Using Windows 2008, 2012 and Server Core Windows Clustering Quorum Failover Clustered Instances Availability Groups Readable Secondaries Clustering Tools and PowerShell Dummies and higher are welcome.
SQL Server High Availability Solutions (Pros & Cons)Hamid J. Fard
Proper SQL Server High Availability Solution Is Highly Depends on the Business Objective and IT Operation Objectives. It Happens Sometimes that We Might Have Few Solutions on the Table to Implement.
If SQL Server is heart of our environment, his health should be very important, right? If SQL Server is important, his availability for our businesses (internal and external) is important to. For our customers doesn't matter where data are stored, how are stored and what we do with those data. Especially for our managers. The data must be available on demand, on time, at he moment of request. High Availability is our responsibility. How we can prepare our environment for HA? How HA is connected for with SLA? And why Service Level Agreement are important for us? In this session I want to discuss about HA options for SQL Server (2008, 2012), about our different customers, and about Service Level Agreement (formal or not).
WebLogic Server Work Managers and Overload ProtectionJames Bayer
A tour of the WebLogic Server work manager and self-tuning thread pool features that automatically adjust to changing workloads and protect the server from overload conditions.
This presentation was given at VMware Partner Exchange (PEX) 2012 in Las Vegas at the EMC boot camp. It provides a comparison of stretched clusters and SRM, and supplies some best practices for building stretched clusters if that is the right solution.
Ramstel - Character design - Tesi di laureaGabriele
Ramstel is my first 3D character. It's the project for my graduation.
I've worked harder to reach the harmony of the parts and the armour was functional to the movement keeping in mind the human biomechanics.
Git is a distributed revision control system with an emphasis on speed, data integrity, and support for distributed, non-linear workflows.
Git is the most widely adopted version control system for software development.
This lecture is a mixture of demo and hands-on. It is suitable for students major in computer science, design, and information technology. Or general public whom want to know how to collaborate better, improve productivity and minimize risk on recover/revert previous work snapshot.
SQL Server AlwaysOn for Dummies SQLSaturday #202 EditionMark Broadbent
Welcome to Microsoft's world of the buzzword. Yes, they've done it again and created another ambiguous term that no one really understands. AlwaysOn is a powerful group of highly available technologies, and in this presentation, we will delve into their murky world & reveal the technology behind the buzz. Focusing specifically on the two key components of SQL Server 2012 AlwaysOn in Failover Clustered Instances and Availability Groups, we will investigate their pre-requisites, setup, administration, use & drawbacks. We will look at: Using Windows 2008, 2012 and Server Core Windows Clustering Quorum Failover Clustered Instances Availability Groups Readable Secondaries Clustering Tools and PowerShell Dummies and higher are welcome.
SQL Server High Availability Solutions (Pros & Cons)Hamid J. Fard
Proper SQL Server High Availability Solution Is Highly Depends on the Business Objective and IT Operation Objectives. It Happens Sometimes that We Might Have Few Solutions on the Table to Implement.
If SQL Server is heart of our environment, his health should be very important, right? If SQL Server is important, his availability for our businesses (internal and external) is important to. For our customers doesn't matter where data are stored, how are stored and what we do with those data. Especially for our managers. The data must be available on demand, on time, at he moment of request. High Availability is our responsibility. How we can prepare our environment for HA? How HA is connected for with SLA? And why Service Level Agreement are important for us? In this session I want to discuss about HA options for SQL Server (2008, 2012), about our different customers, and about Service Level Agreement (formal or not).
WebLogic Server Work Managers and Overload ProtectionJames Bayer
A tour of the WebLogic Server work manager and self-tuning thread pool features that automatically adjust to changing workloads and protect the server from overload conditions.
This presentation was given at VMware Partner Exchange (PEX) 2012 in Las Vegas at the EMC boot camp. It provides a comparison of stretched clusters and SRM, and supplies some best practices for building stretched clusters if that is the right solution.
Ramstel - Character design - Tesi di laureaGabriele
Ramstel is my first 3D character. It's the project for my graduation.
I've worked harder to reach the harmony of the parts and the armour was functional to the movement keeping in mind the human biomechanics.
Git is a distributed revision control system with an emphasis on speed, data integrity, and support for distributed, non-linear workflows.
Git is the most widely adopted version control system for software development.
This lecture is a mixture of demo and hands-on. It is suitable for students major in computer science, design, and information technology. Or general public whom want to know how to collaborate better, improve productivity and minimize risk on recover/revert previous work snapshot.
SQLSaturday Bulgaria : HA & DR with SQL Server AlwaysOn Availability Groupsturgaysahtiyan
The AlwaysOn Availability Groups feature is a high-availability and disaster-recovery solution that provides an enterprise-level alternative to database mirroring. Introduced in SQL Server 2012, AlwaysOn Availability Groups maximizes the availability of a set of user databases for an enterprise. In this session we will talk about what’s coming with Always On, and how does it help to improve high availability and disaster recovery solutions.
Continuent Tungsten - Scalable Saa S Data Managementguest2e11e8
The key needs of SaaS vendors include:
i) managing multi-tenant architectures with shared DBMS, ii) maintaining customer SLAs for uptime and performance and iii) optimized, efficient operations.
The key benefits Continuent Tungsten offers SaaS vendors are:
i) high availability and protection from data loss, ii) simple, efficient cluster management and iii) enable complex database topologies.
Tungsten offers high-availability, database cluster management and management of complex topologies for multi-tenant architectures.
Tungsten high availability and data protection features include maintaining live copies with data consistency checking and tightly coupled backup/restore integration with cluster management tools.
Tungsten cluster management allows SaaS vendors to migrate customers and perform system upgrades without downtime, thus enabling these maintenance operations during normal business hours.
Tungsten also enables complex replication topologies, including data filtering and data archiving strategies, maintaining extra data copies for data-marts, routing different customers to different DBMS copies, and providing cross-site multi-master replication.
SQL Server Alwayson for SharePoint HA/DR Step by Step GuideLars Platzdasch
SQL Server Alwayson for Sharepoint HA/DR SQL Konferenz 2017
-What is SQL Server AlwaysOn?
-AlwaysOn Failover Clustering
-AlwaysOn Availability Groups
-Why AlwaysOn Availability Groups for SharePoint?
-Requirements and Prerequisites
-Step by Step guide to implementing AlwaysOn Availability Groups
Demonstration
lessons learned
SharePoint 24x7x365 Architecting for High Availability, Fault Tolerance and D...Eric Shupps
Building SharePoint farms for development and testing is easy. But building highly available farms to meet enterprise service level agreements that are fault tolerant, scalable and fully recoverable? Not so simple. Learn how to plan, design and implement a highly available on-premises farm architecture for 2016 and 2019 using proven, field-tested techniques and practical guidance.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
1. SQL Server 2012
High Availability
and DR
Northern Virginia SQL Users
Group
23-January-2012
2. About Me
@jdanton on Twitter
Joedantoni.wordpress.com
Videos and Blogs at SSWUG.org
Vice President of the Philadelphia SQL
Server UG
3. Agenda
Licensing Changes
SQL Server 2008 to 2012—What’s
Changed in HA and DR
Geo-Clustering
All about Availability Groups
4. Learning Objectives
SQLServer HA and DR
What involved in SQL Clustering
How it works
What’s new in 2012 HA/DR
This
presentation is geared towards
DBAs—so feel free to stop at any time with
questions
5. High Availability and DR
Options in SQL 2008
SQL Server Clustering
SQL Server Mirroring
Peer to Peer Replication
SQL Server Log Shipping*
6. Licensing (What’s changed)
The Availability Group features will require
the Enterprise Edition of SQL Server
The licensing model for SQL Enterprise
Edition has changed. Consult your friendly
Microsoft sales representative for more
details
Mirroring is listed as being deprecated
from Standard Edition. Will still be there in
2012
7. SQL Server 2012
Extended Events are used much more
heavily
Slipstream Install no longer required—SQL
will check for updates from your Windows
Update source
Can use internet Windows Update or
internal source
8. Windows Core Support
No GUI version of Windows
Allows for fewer patches
Uses PowerShell and MMCs for support
10. HA and DR Options in SQL
Server 2012
Backup and Recovery
Mirroring
Availability Groups (2012)
Log Shipping
Replication
SAN Replication*
Virtualization*
11. What’s new in SQL Server 2012
HA/DR
Multi-subnet clustering is supported
Flexible Failover
The BIG one—Always On Availability
Groups
13. Clustering--2008
SQL Clustering required 1 subnet to be
used across the whole cluster
Cluster failover is controlled by
isAlive/looksAlive processes, which check
the SQL service and run @@servername
14. Clustering 2012
Fullsupport for geo-distributed clusters
Flexible failover model
TempDB on Non-shared Disk Resource
Makes PCI-based Solid State Drive an
option
No check for this as of CTP3—instance
won’t start if TempDB drive location not
available
17. Geo-Distributed Clustering
Requires SAN replication ($$$$)
Two of everything
Requires really fast network connection
Requires some trickery at the
network/DNS level for connectivity
New Term: Witness Disk
Can be physical (SAN) disk, or cluster file
share
19. Takeaway 2012
Thisfeature was available in 2008, just
much more complicated to implement
from a network perspective
Won’t be used by 95% of organizations
20. Why Do Clusters Failover?
• Initiated by failures in
hardware or software
• Checked by
isAlive/LooksAlive
processes (in 2008R2
and below)
21. Flexible Failover
Replaces looksAlive/isAlive functionality in
SQL Clusters (and is used for Availability
Groups)
Now runs sp_server_diagnostics
Two new parameters
HealthCheckTimeout (Default 60
sec/Minimum 15 sec)
Failover Condition Level
22. Flexible Failover Policies for
Clusters
Level Condition Description
No automatic failover • Indicates that no failover or restart will be triggered
0
or restart automatically on any failure conditions.
Failover or restart on
1 • SQL Server service is down.
server down
• SQL Server instance is not responsive (Resource DLL cannot
Failover or restart on
2 receive data from sp_server_diagnostics within the
server unresponsive
HealthCheckTimeout settings).
Failover or restart on • System stored procedure sp_server_diagnostics returns
3 (Default)
critical server errors ‘system error’. (Critical errors > 20)
Failover or restart on • System stored procedure sp_server_diagnostics returns
4
moderate server errors ‘resource error’. (Moderate errors > 17)
Failover or restart on
• System stored procedure sp_server_diagnostics returns
5 any qualified failure
‘query_processing error’. (Deadlock)
conditions
24. Understanding Quorum
There are a few slides on this topic, it’s a
little confusing
In a nutshell, you cluster has to be able to
talk to itself to keep the cluster service up in
running
This applies to both SQL Server Failover
Cluster Instances and AlwaysOn Availability
Groups
25. Quorum
Quorum is critical—contains master copy
of the cluster’s configuration
Serves as a tiebreaker if network
communications between cluster nodes
fail
If Quorum fails—cluster is shut down until
it’s restored
26. Quorum Models
Node and Disk Majority (Default)
Node Majority
No Majority (Quorum Disk Only)
Node and File Share Majority (Good for
Geo Clusters)
27. Quorum Failure Tolerance
Number of Nodes 2 3 4 5 6 7
Node Majority 0 1 1 2 2 3
Node and Disk/File Share Majority 1 2 2 3 3 4
• Assuming Disk is Up Calculation is: Cluster Up = RoundUp(Total
# of Nodes/2)
• Assuming Disk is Down Calculation is: ClusterUp = RoundUp
(Total # of Nodes/2)-1
28. DR in SQL 2008
Mirroring
Allowed automatic failover, but only one
target
Mirror target is unreadable
Log Shipping
Allowed multiple targets, but failover a
manual process, requiring a connection
string change
Replication
30. AlwaysOn Requirements
Windows Enterprise (Clustering is a
requirement)
SQL Server Enterprise Edition
Windows Cluster
No shared storage is required
Quorum Disk Preferred
31.
32. Flexible AG Failover
Similar to how a failover clustered
instance fails over
Connects to instance every 30 seconds to
perform health check
Also, similar quorum model to Windows
Failover Clustering
33. Allows for SAN Less HA/DR
Thisisn’t a huge thing for SQL Server at big
shops
It may allow us to incorporate a level of
DR into a virtual environment
34. Client Connections in This
Model
Availability
Group Listener (Yes, SQL Server
now has a listener)
Works just like a failover clustering instance
(single instance, single IP)
Creates a VCO (AD Virtual Computer
Object)
35. Contained Databases
Isolate Database from Instance
Currently only fully supported with SQL
Logins
No numbered procedures
Eases database movement
Allows for ease of migration to Azure
Not quite baked out as of RC0
36. Read Only Replicas
Can have up to 3
SQL Client 2012 will allow for this routing
specifically
Can take backups from read-only copys*
Copy Only Backups (only full copy, does
not affect primary log)
Indexingmust be same on replicas
Bad queries can affect status of replica
37. Considerations for Availability
Groups
All SQL servers (including the secondary in the
DR site) in the same Windows domain
All the databases must be in FULL recovery
model
The unit of failover (for local HA, as well as DR)
is at the AG level, i.e., group of databases –
not the instance
No delayed apply on the secondary
Removing log shipping means the regular log
backup job is removed
Need to re-establish periodic log backup
(essential for truncating the log)
38. Failover Modes
Automatic failover
Planned manual failover (without data
loss)
Forced manual failover (with possible
data loss)
39. Failover
Synchronous- Synchronous-
Asynchronous- commit mode commit mode
commit mode with manual- with automatic-
failover mode failover mode
Automatic
No No Yes
failover
Manual failover No Yes Yes
Forced failover Yes Yes No
41. Summary
Lotsof Change in the HA/DR Space
Licensing also changes—talk to your MS
rep
SQL Server Failover Clusters still a good HA
option
AlwaysOn Availability Groups add a lot
more flexibility to DR
SQL Server clustering is the most obvious high availability solution that everyone knows about. However, mirroring between two SQL Servers (with a witness server) can also provide a level a both h/a and D/R. The other two options are a little bit more controversial and more complicated to setup. Both peer to peer replication and SQL Log Shipping can provide some measure of H/A, but there are caveats to this, and some data loss is possible. This is a little outside of the scope of this preso, so if you would like to know more detail around these topics, I highly recommend Paul Randal’s white paper on SQL HA and DR options. I’ll provide a link at the end of this presentation.
Extended Events came out in SQL Server 2008, but very few people, myself included, paid much attention. Those who did found the implementation awkward and confusing. Only a few people persevered enough to discover just how powerful and amazing these things are. Which is why most anyone who wants to learn about extended events should plan on starting at one place, Jonathan Kehayias’ blog. Yeah, the Books Online help get you started, but Jonathan really makes it all take off.
DR Options—yes backup and recovery is your first line of defense in the event of a disaster. You should have extensive monitoring and notification around your backup process, and take regular transaction log backups, if you need point in time recovery.Mirroring is probably the best high availability option. With a witness server (a server that sits in between the two mirrors) you get automatic failover in the event of the failure of your primary instance goes down. Most applications that use Microsoft connections to your database can support mirroring. The only negative, is that unless you have enterprise edition, you are limited to synchronous mirroring, which can have a performance impact on your primary. Enterprise edition brings in asynchronous mirroring, which allows for greater flexibility and distance between sites with no performance impact.Log shipping and Replication—both of these will require manual intervention in the event of a failure. However, they are very mature technologies and can work over great distances. This is not a DR scenario, but I have an application which replicates from the US to Switzerland over a nominal network connection, running on SQL 2000, and I haven’t had to touch it in two years. (Knocks on wood).Lastly SAN replication—this is really cool technology, and can enable the concept of geo-distributed clusters (also covered in Paul’s white paper). This is pretty far out of scope for today’s presentation, but I’ll say this—while really cool, it’s really complex to setup, and really expensive. You need additional software from your SAN vendor, which is always pretty pricey, and the additional network bandwidth to transfer bits in real time over the network. When I was at Wyeth, we did this between Philadelphia and Pearl River NY for the SAP system that ran the business. But the cost made it prohibitive to do much else. Also, when it goes wrong, it can be ugly.
Insert picture here
A partially contained database is a contained database that allows the use of uncontained features. Partially contained databases do not allow the following actions or entities. Numbered proceduresSchema-bound objects that depend on built-in functions with collation changesBinding change resulting from collation changes, including references to objects, columns, symbols, or types.Replication, change data capture, and change tracking.Use the sys.dm_db_uncontained_entities and sys.sql_modules (Transact-SQL) view to return information about uncontained objects or features. By determining the containment status of the elements of your applications, you can discover what objects or features need to be replaced or altered for use in a fully contained database.
Automatic failoverAutomatic failover is supported only when the current primary and one secondary replica are both configured with failover mode set to AUTOMATIC and the secondary replica currently synchronized. If the failover mode of either the primary or secondary replica is MANUAL, automatic failover cannot occur. Occurs only between a primary replica and a secondary replica that are configured for synchronous-commit mode and automatic failover mode when the secondary replica is in the SYNCHRONIZED state.Planned manual failover (without data loss)Planned manual failover, or manual failover, is useful for administrative purposes. It is supported only if both the primary replica and secondary replica are configured for synchronous-commit mode and the secondary replica is currently synchronized (in the SYNCHRONIZED state). A database administrator manually initiates a manual failover.Forced manual failover (with possible data loss)Intended only for disaster recovery, forced manual failover, or forced failover, is supported only when the synchronization health of the target availability replica either NOT_SYNCHRONIZING or SYNCHRONIZING. This is the only form of failover supported by in asynchronous-commit availability mode.Automatic failover setExists only when a pair of availability replicas (including the current primary replica) are configured for synchronous-commit mode with automatic failover, if any. An automatic failover set takes effect only if the secondary replica is currently SYNCHRONIZED with the primary replica. Synchronous-commit failover setExists only when a set of two or three availability replicas (including the current primary replica) are configured for synchronous-commit mode. A synchronous-commit failover set takes effect only if the secondary replicas are configured for manual failover mode and at least one secondary replica is currently SYNCHRONIZED with the primary replica. Entire failover setWithin a given availability group, the set of all availability replicas whose operational state is currently ONLINE, regardless of availability mode and of failover mode. The entire failover set becomes relevant when no secondary replica is currently SYNCHRONIZED with the primary replica.
The amount of time that the database will be unavailable during a failover depends on the type of failover and its cause. For more information, see Estimate the Interruption of Service During Failover of an Availability Group (SQL Server). ImportantTo support client connections after failover, except for contained databases, logins and jobs defined on any of the former primary databases must be manually recreated on the new primary database. For more information, see Management of Logins and Jobs for the Databases of an Availability Group (SQL Server).