Tuesday, 22 September 2015

Clustering FAQ

Here are a few of our Frequently Asked Questions:

Can i cluster virtualized servers?

Yes, you can create failover clusters with virtual servers with VMware or Hyper-V.


Which OS do i need?

Since Windows Server 2008, Microsoft has incorporated a useful failover cluster feature, which many businesses use today, but you are not bound to a Microsoft platform, as there are many different solutions that offer the same services for Linux. It is worth noting that Windows server must be of the Enterprise or Datacenter variety.


Do i need shared storage (SAN/NAS)?


No, there are many tools out there that allow you to utilize the local storage of the server. For example SIOS Datakeeper enables you to create a shared partition on the local drives, which are then mirrored.


What is Quorum?


Quorum is design to help prevent split brain, this is where multiple nodes in the cluster try to own the workload and write to the same disk, which can lead to problems. Quorum is based on a calculation of votes, where each node has a single vote in determining the overall cluster health.

Tuesday, 8 September 2015

SIOS DataKeeper v8.3.0 is here!

Great news! SIOS have released there latest version of the DataKeeper solution, this new release provides new features and bug fixes, as well as adding new platform support.

New Features:

Notification Icon in the system tray
Powershell cmdlet support
Healthcheck CLI for mirror status
Oracle 12c Support
Additionally, this release includes:

General maintenance
Bug Fixes
Support tool improvements


For complete details on version v8.3.0 please refer to the release notes.


Thursday, 3 September 2015

SQL Relay

About SQL Relay:

Setup in 2011, SQL relay’s main focus is to raise awareness of the UK SQL Server community. What started off as a handful of user groups, over the years has evolved into an 8-day relay around the country, bringing excellent speakers to the community with tons of free education for users!As SQL Relays embarks on it sixth conference, it is still very much community driven and works to support their needs, meaning a broadening of topics into cloud and analytic's. SQL Relay is organised by user group leaders, speakers, and active community members.

Edinburgh                    (5/10/2015)                  Summerhall, 1 Summerhall, Edinburgh, EH9 1PL
Huddersfield                (6/10/2015)                  Cathedral House, St Thomas Road, Huddersfield, HD1 3LG,
Nottingham                  (7/10/2015)                  Albert Hall, N Circus Street, Nottingham, NG1 5AA
London                         (8/10/2015)                  Microsoft, Cardinal Place, 80-100 Victoria Street, London, SW1E 5JL
Reading                        (12/10/2015)                Microsoft Reading, Thames Valley Park, Earley, RG6 1WA
Bristo
l                           (13/10/2015)                Future Inns, Bond Street, Bristol, BS1 3EN
Cardiff                           (14/10/2015)                Motorpoint Arena, Mary Ann Street, Cardiff, CF10 2JH,
Birmingham                 (15/10/2015)                MAC Centre, Cannon Hill Park, Birmingham, B12 9QH,

What’s included in the SQL Relay?

There are 4 tracks covering SQL Server, Business Intelligence, and Analytics. This will be split by 3 tracks of 1hr sessions, plus a workshop track.Topics covered will include:

·         SQL Server performance
·         Management and development
·         Azure/Cloud technology
·         Big data
·         Cubes
·         Reporting and dash boarding
There will be something to suit everyone, whether an accidental DBA, a hotshot BI pro, or a jack of all trades!


To find out more please visit www.SQLrelay.co.uk


If you would like to find out more about your local SQL user group please below table:


SQL Group
Website
Belfast
Cambridge
Cardiff
Hertfordshire
Manchester
Midlands
East Midlands
Reading
Southampton
London
Northeast (Newcastle)
Ireland

Cork

South West
 

Tuesday, 25 August 2015

SQL Saturday #418– Manchester 2015 Review





The day kicked off with registration and breakfast. The breakfast was a continental breakfast with good options for both vegetarians and non-vegetarians (a real thumbs up, beats the normal bacon butties!)


The room was arranged as Red gate, Pyramid, Evolution, SanDisk, Calibri, Dell, Microsoft, SQL Pass, Big Bang Data, Purple Frogs and SIOS Technology.
There was a welcome speech followed by Keynotes and then the sessions began. A summary of the sessions is given below:

The sessions on the whole were good and informative. Definitely something to help increase awareness within IT and open up ideas to new technologies.
Here are a few pictures from the day.








All in all a wonderful event and something anyone working with SQL should attend as it is full of resources and free education.
See you at the next SQL event… SQL Relay October 5th – 15th.


Monday, 24 August 2015

Introduction to Failover Clustering

Introduction

This is a guide for the installation and configuration of failover clustering on windows.
We will create a simple two node cluster, and configure a file server service which will be protected. The guide is split into 4 main activities:

Connect the cluster servers to the network and storage
Install the failover clustering feature
Create the Cluster
Configure the Fileserver


Connect the cluster servers to the network and storage

For a failover cluster network, it is ideal to avoid having single points of failure. There are multiple ways of accomplishing this.
1.     You can connect your cluster nodes by multiple, distinct networks.

2.       You can connect your cluster nodes with one network that is constructed with teamed network adaptors, redundant switches, redundant routers, or similar hardware that removes single points of failure.
Ensure that you can ping all devices on the network before continuing.

Install the failover clustering feature

  1. Click Start, click Administrative Tools, and then click Server Manager.

In Server Manager, under Features Summary, click Add Features.
  1. In the Add Features Wizard, click Failover Clustering, and then click Install.
  2. Follow the instructions in the wizard to complete the installation of the feature. When the wizard finishes, close it.
  3. Repeat the process for each server that you want to include in the cluster.


Install the File Server feature
  1. Click Start, click Administrative Tools, and then click Server Manager.

In Server Manager, under Features Summary, click Add Features.
  1. In the Add Features Wizard, click Failover Clustering, and then click Install.
  2. Follow the instructions in the wizard to complete the installation of the feature. When the wizard finishes, close it.
  3. Repeat the process for each server that you want to include in the cluster.


Create the Cluster

  1. Click Start, click Administrative Tools, and then click Failover Cluster Management.
  2. Confirm that Failover Cluster Management is selected and then, in the center pane under Management, click Create a cluster.

Follow the instructions in the wizard to specify:
    • The servers to include in the cluster.
    • The name of the cluster.
    • Any IP address information that is not automatically supplied by your DHCP settings.
  1. After the wizard runs and the Summary page appears, to view a report of the tasks the wizard performed, click View Report.


Configure the Fileserver

  1. Click Start, click Administrative Tools, and then click Failover Cluster Management.
  2. In the console tree, if the cluster that you created is not displayed, right-click Failover Cluster Management, click Manage a Cluster, and then select the cluster you want to configure.
  3. In the console tree, click the plus sign next to the cluster that you created to expand the items underneath it.
  4. Click Services and Applications. Under Actions (on the right), click Configure a Service or Application.

  1. Review the text on the first page of the wizard, and then click Next.

  1. Click File Server, and then click Next.
  2. Follow the instructions in the wizard to specify the following details:
    • A name for the clustered file server
    • Any IP address information that is not automatically supplied by your DHCP settings—for example, a static IPv4 address for this clustered file server
    • The storage volume or volumes that the clustered file server should use
  3. After the wizard runs and the Summary page appears, to view a report of the tasks the wizard performed, click View Report.
  4. To close the wizard, click Finish.
  5. In the console tree, make sure Services and Applications is expanded, and then select the clustered file server that you just created.
  6. Under Actions, click Add a shared folder.
  7. Follow the instructions in the wizard to specify the following settings for the shared folder:
    • Path and name.
    • TFS permissions (optional).
    • Advanced settings for the SMB protocol (optional). SMB is used by Windows-based clients. The settings include:

      - User limits.

      - Offline settings (caching).

      - Access-based enumeration
    • Whether the NFS protocol will be used, for support of UNIX-based clients (optional).
  8. After completing the wizard, confirm that the clustered file server comes online. If it does not, review the state of the networks and storage and correct any issues. Then right-click the new clustered file server and click Bring this service or application online.
  9. To perform a basic test of failover, right-click the clustered file server, click Move this service or application to another node, and click the available choice of node. When prompted, confirm your choice.
You can observe the status changes in the center pane of the snap-in as the clustered file server instance is moved.

And now you should have a fully functioning and protected File Server.




Monday, 17 August 2015

Introduction to clustering

Here is a brief overview of the different types of clustering, and their purposes for different applications.

High Availability

                In information technology, high availability refers to a system or component that is continuously operational for a desirably long length of time. Availability can be measured relative to "100% operational" or "never failing." A widely-held but difficult-to-achieve standard of availability for a system or product is known as "five 9s" (99.999 percent) availability. Since a computer system or a network consists of many parts in which all parts usually need to be present in order for the whole to be operational, much planning for high availability centers around backup and fail-over processing and data storage and access. For storage, a redundant array of independent disks (RAID) is one approach. A more recent approach is the storage area network (SAN).
Some availability experts emphasize that, for any system to be highly available, the parts of a system should be well-designed and thoroughly tested before they are used. For example, a new application program that has not been thoroughly tested is likely to become a frequent point-of-breakdown in a production system.


Disaster Recover

Disaster recovery is the area of security planning that deals with protecting an organization from the effects of significant negative events. Significant negative events, in this context, can include anything that puts an organization’s operations at risk: crippling cyber attacks and equipment failures, for example, as well as hurricanes, earthquakes and other natural disasters. A disaster recovery plan (DRP) documents policies, procedures and actions to limit the disruption to an organization in the wake of a disaster. Just as a disaster is an event that makes the continuation of normal functions impossible, a disaster recovery plan consists of actions intended to minimize the negative effects of a disaster and allow the organization to maintain or quickly resume mission-critical functions. In information technology, disaster recovery steps may include restoring servers or mainframes with backups, re-establishing private branch exchanges (PBX) or provisioning local area networks (LANs) to meet immediate business needs. Business continuity describes the processes and procedures an organization must put in place to ensure that mission-critical business functions can continue during and after a disaster. The emphasis is more on maintaining business operations than IT infrastructure. Because business continuity and disaster recovery are so closely related, the two terms are sometimes combined as Business Continuity and Disaster Recovery (BCDR or BC/DR).


Load Balancing

Load balancing is dividing the amount of work that a computer has to do between two or more computers so that more work gets done in the same amount of time and, in general, all users get served faster. Load balancing can be implemented with hardware, software, or a combination of both. Typically, load balancing is the main reason for computer server clustering. On the Internet, companies whose Web sites get a great deal of traffic usually use load balancing. For load balancing Web traffic, there are several approaches. For Web serving, one approach is to route each request in turn to a different server host address in a domain name system (DNS) table, round-robin fashion. Usually, if two servers are used to balance a work load, a third server is needed to determine which server to assign the work to. Since load balancing requires multiple servers, it is usually combined with fail-over and backup services. In some approaches, the servers are distributed over different geographic locations.


High Performance clustering

High-performance computing (HPC) is the use of parallel processing for running advanced application programs efficiently, reliably and quickly. The term applies especially to systems that function above a teraflop or 1012 floating-point operations per second. The term HPC is occasionally used as a synonym for super computing, although technically a super computer is a system that performs at or near the currently highest operational rate for computers. Some supercomputers work at more than a petaflop or 1015 floating-point operations per second. The most common users of HPC systems are scientific researchers, engineers and academic institutions. Some government agencies, particularly the military, also rely on HPC for complex applications. High-performance systems often use custom-made components in addition to so-called commodity components. As demand for processing power and speed grows, HPC will likely interest businesses of all sizes, particularly for transaction processing and data warehouses. An occasional techno-fiends might use an HPC system to satisfy an exceptional desire for advanced technology.