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Disaster recovery(DR) must be reliable, speedy and economical. These are the basic requirements for all businesses, and small to medium-sized enterprises (SMEs) are no exception. But, for smaller firms, cost considerations will be at or near the top of the IT managers list.

Organisations often view disaster recovery as little more than insurance, or as IDC analyst Phil Goodwin puts it, an expense that is likely to have little payback.

Large firms in highly regulated markets such as financial services invest heavily in disaster recovery and business continuity, not least because they are mandated to do so.

RBS, for example, was fined 56m for an IT failure in 2012.

Smaller firms might not have the budget for DR, however. Or they might choose not to pay for it, hoping they can ride out any incident with backups and hard work. This is short-sighted.

The Uptime Institutes 2018 Global Data Center Surveyfound that 31% of businesses experienced downtime that caused severe damage, but that 80% of incidents could have been prevented.

Operating disaster recovery on a pay-as-you-go model, combined with faster data transfers over the public internet, is transforming DR options for SMEs

Disaster recovery is becoming cheaper, simpler and more effective, through the growth of cloud-based services.

Firms no longer need to invest in dedicated or duplicate hardware, remote datacentres and the skilled staff to maintain them. Cloud or hybrid cloud technologies allow smaller companies to outsource much of the technical side of DR provision and to move to an on-demand model.

Operating disaster recovery on a pay-as-you-go model, combined with faster data transfers over the public internet, is transforming DR options for SMEs.

For smaller firms, conventional backup and disaster recovery has long meant saving data to tape or other removable media and storing it off-site. In case of a disaster the firm would need to source new hardware and restore data and applications.

Larger or better-resourced businesses, or those depending heavily on their data, will have invested in automatic off-site data replication and even standby servers. Others contracted with specialist suppliers to manage DR.

In the past, DR meant having a redundant location that was either always-on, a hot DR facility, or the use of shared resources that would be configured and set up when needed, says Roy Illsley, a distinguished analyst at Ovum who covers infrastructure solutions. These solutions are typically expensive or bring long recovery times.

Some businesses have moved to ad-hoc cloud backup solutions, including consumer-grade online storage. But this is still labour-intensive.

Small and medium-sized enterprises often deem disaster recovery too expensive or peripheral to core operations to fully invest in, warns Mark Wass, a director at business continuity supplier Sungard.

They often settle for a DIY, cloud-based platform approach, which they believe to be cheaper, and then assign responsibility for managing it to the office manager, he says.

Although this avoids reliance on on-site backups, it is still a manual process. And, Wass says, assuming staff can rely on cloud-based storage and access to a personal device to work on is risky.

Fortunately, the market for online disaster recovery is growing, and so is the choice of suppliers. Companies such as Veeam, Rubrik, Commvault, Cohesity and Nutanix provide options for businesses that need an off-the-shelf solution.

Cloud-based DR is available either directly from suppliers, or through managed service providers and IT integrators.

OGL Computer is a managed service provider with 1,200 UK SME customers. It offers a choice of cloud recovery and cloud-based data replication, as well as dedicated recovery options for VMware and Hyper-V. Recovery allows firms to restore their key applications within 24 hours cloud-based replication provides recovery within seconds.

But, as OGLs enterprise solutions architect, Steve Bennett, says, there are also customers who need, or prefer, an on-premise solution.

The availability of cloud services is an obvious way backup is becoming easier for SMEs, says Bryan Betts, analyst at Freeform Dynamics. But if they cant or dont want to use cloud, theres also the appliance option, either physical or virtual.

The availability of cloud services is an obvious way backup is becoming easier for SMEs. But if they cant or dont want to use cloud, theres also the appliance option, either physical or virtual Bryan Betts, Freeform Dynamics

Add in the availability of flash storage and modern software that provides user self-service, and you can get a box that not only takes care of all or almost all your backups, but also lets users themselves quickly sort out most of their data recovery needs.

Changes in the way businesses buy technology are also affecting disaster recovery.

Hyper-converged infrastructure (HCI) started out as a way to make it easier to deploy virtual machines. But because hyper-converged systems usually include their own storage, they lend themselves to disaster recovery too. On-premise HCI systems can be out of the reach of SMEs, but the implementation of cloud-based HCI makes it much more accessible.

An example is Cohesitys Clusters, but Nutanix and Rubrik use similar technologies. Businesses with the in-house expertise can also look at replication to enterprise public cloud providers, such as Amazon Web Services, Microsoft Azure and Google Cloud Platform.

Cloud DR isnt [as] neatly packaged but is more flexible, says Peter Groucutt, managing director of backup provider Databarracks. You can choose your replication software, such as ASR, Zerto or Veeam, and choose your cloud platform. For day-to-day replication you can keep cloud resources to a minimum but have the resources available to scale up as much as you need when you invoke DR.

Another factor in favour of a bespoke approach is the growing need to back up cloud-based applications. The appliance-to-offsite-backup or appliance-to-cloud route is tried and tested, but data backups from cloud-based applications are largely best kept in the cloud.

IT managers should check their disaster recovery plan includes cloud applications. More software-as-a-service (SaaS) providers are including application availability and data protection options with their products.

No amount of technology, though, will protect a business if it fails to work. This means having a disaster recovery plan, a robust testing regimeand a plan to deal with human factors, from the availability of technical experts to senior managements ability to act under pressure.

You must have a robust process that has clear rules on when a switch to disaster recovery is required and when it is not Roy Illsley, Ovum

For SMEs, the main point to consider is ease of use in setting up the replication, and then how the DR capability can be tested and verified it is operating and fit for purpose, says Ovums Illsley. The area where most SMEs fail is in the process for invoking the DR plan. You must have a robust process that has clear rules on when a switch to DR is required and when it is not.

Freeform Dynamics Betts goes further. The absolutely key requirement for DR is to make sure you can recover, he warns. Test it often enough to make sure not just that your backup process is reliable, but that you can rebuild a working system from it within the specified recovery time objective and recovery point objective.

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SME disaster recovery made easy with cloud, hybrid and HCI - ComputerWeekly.com

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When you want to use Linux to provide services to a business, those services will need to be secure, resilient and scalable. Nice words, but what do we mean by them?

Secure means that users can access to the data they require, be that read-only access or write access. At the same time, no data is exposed to any party thats not authorised to see it. Security is deceptive: you can think you have everything protected only to find out later that there are holes. Designing in security from the start of a project is far easier than trying to retrofit it later.

Resilient means your services tolerate failures within the infrastructure. A failure might be a server disk controller that can no longer access any disks, rendering the data unreachable. Or the failure might be a network switch that no longer enables two or more systems to communicate. In this context, a single point of failure or SPOF is a failure that adversely affects service availability. A resilient infrastructure is one with no SPOFs.

Scalable describes the ability of systems to handle spikes of demand gracefully. It also dictates how easily changes may be made to systems. For example, adding a new user, increasing the storage capacity or moving an infrastructure from Amazon Web Services to Google Cloud or even moving it in-house.

As soon as your infrastructure expands beyond one server, there are lots of options for increasing the security, resilience and scalability. Well look at how these problems have been solved traditionally, and what new technology is available that changes the face of big application computing.

(Image credit: Future)

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To understand whats possible today, its helpful to look at how technology projects have been traditionally implemented. Back in the olden days that is, more than 10 years ago businesses would buy or lease hardware to run all the components of their applications. Even relatively simple applications, such as a WordPress website, have multiple components. In the case of WordPress, a MySQL database is needed along with a web server, such as Apache, and a way of handling PHP code. So, theyd build a server, set up Apache, PHP and MySQL, install WordPress and off theyd go.

By and large, that worked. It worked well enough that there are still a huge number of servers configured in exactly that way today. But it wasnt perfect, and two of the bigger problems were resilience and scalability.

Lack of resilience meant that any significant issue on the server would result in a loss of service. Clearly a catastrophic failure would mean no website, but there was also no room to carry out scheduled maintenance without impacting the website. Even installing and activating a routine security update for Apache would necessitate a few seconds outage for the website.

The resilience problem was largely solved by building high availability clusters. The principle was to have two servers running the website, configured such that the failure of either one didnt result in the website being down. The service being provided was resilient even if the individual servers were not.

Part of the power of Kubernetes is the abstraction it offers. From a developers perspective, they develop the application to run in a Docker container. Docker doesnt care whether its running on Windows, Linux or some other operating system. That same Docker container can be taken from the developers MacBook and run under Kubernetes without any modification.

The Kubernetes installation itself can be a single machine. Of course, a lot of the benefits of Kubernetes wont be available: there will be no auto-scaling; theres an obvious single point of failure, and so on. As a proof of concept in a test environment, though, it works.

Once youre ready for production, you can run in-house or on a Cloud provider such as AWS or Google Cloud. The Cloud providers have some built-in services that assist in running Kubernetes, but none of are hard requirements. If you want to move between Google, Amazon and your own infrastructure, you set up Kubernetes and move across. None of your applications have to change in any way.

And where is Linux? Kubernetes runs on Linux, but the operating system is invisible to the applications. This is a significant step in the maturity and usability of IT infrastructures.

The scalability problem is a bit trickier. Lets say your WordPress site gets 1,000 visitors a month. One day, your business is mentioned on Radio 4 or breakfast TV. Suddenly, you get more than a months worth of visitors in 20 minutes. Weve all heard stories of websites crashing, and thats typically why: a lack of scalability.

The two servers that helped with resilience could manage a higher workload than one server alone could, but thats still limited. Youd be paying for two servers 100 per cent of the time and most of the time both were working perfectly. Its likely that one alone could run your site. Then John Humphrys mentions your business on Today and youd need 10 servers to handle the load but only for a few hours.

The better solution to both the resilience and scalability problem was cloud computing. Set up a server instance or two the little servers that run your applications on Amazon Web Services (AWS) or Google Cloud, and if one of the instances failed for some reason, it would automatically be restarted. Set up auto-scaling correctly and when Mr Humphrys causes the workload on your web server instances to rapidly rise, additional server instances are automatically started to share the workload. Later, as interest dies down, those additional instances are stopped, and you only pay for what you use. Perfect or is it?

Whilst the cloud solution is much more flexible than the traditional standalone server, there are still issues. Updating all the running cloud instances isnt straightforward. Developing for the cloud has challenges too: the laptop your developers are using may be similar to the cloud instance, but its not the same. If you commit to AWS, migrating to Google Cloud is a complex undertaking. And suppose, for whatever reason, you simply dont want to hand over your computing to Amazon, Google or Microsoft?

Containers have emerged as a means to wrap applications with all of their dependencies up into a single package that can be run anywhere. Containers, such as Docker, can run on your developers laptops in the same way as they run on your cloud instances, but managing a fleet of containers becomes increasingly challenging as the number of containers grows.

The answer is container orchestration. This is a significant shift in focus. Before, we made sure we had enough servers, be they physical or virtual, to ensure we could service the workload. Using the cloud providers autoscaling helped, but we were still dealing with instances. We had to configure load balancers, firewalls, data storage and more manually. With container orchestration, all of that (and much more) is taken care of. We specify the results we require and our container orchestration tools fulfil our requirements. We specify what we want done, rather than how we want it done.

Kubernetes (ku-ber-net-eez) is the leading container orchestration tool today, and it came from Google. If anyone knows how to run huge-scale IT infrastructures, Google does. The origin of Kubernetes is Borg, an internal Google project thats still used to run most of Googles applications including its search engine, Gmail, Google Maps and more. Borg was a secret until Google published a paper about it in 2015, but the paper made it very apparent that Borg was the principal inspiration behind Kubernetes.

Borg is a system that manages computational resources in Googles data centres and keeps Googles applications, both production and otherwise, running despite hardware failure, resource exhaustion or other issues occurring that might otherwise have caused an outage. It does this by carefully monitoring the thousands of nodes that make up a Borg cell and the containers running on them, and starting or stopping containers as required in response to problems or fluctuations in load.

Kubernetes itself was born out of Googles GIFEE (Googles Infrastructure For Everyone Else) initiative, and was designed to be a friendlier version of Borg that could be useful outside Google. It was donated to the Linux Foundation in 2015 through the formation of the Cloud Native Computing Foundation (CNCF).

Kubernetes provides a system whereby you declare your containerised applications and services, and it makes sure your applications run according to those declarations. If your programs require external resources, such as storage or load balancers, Kubernetes can provision those automatically. It can scale your applications up or down to keep up with changes in load, and can even scale your whole cluster when required. Your programs components dont even need to know where theyre running: Kubernetes provides internal naming services to applications so that they can connect to wp_mysql and be automatically connected to the correct resource.

The end result is a platform that can be used to run your applications on any infrastructure, from a single machine through an on-premise rack of systems to cloud-based fleets of virtual machines running on any major cloud provider, all using the same containers and configuration. Kubernetes is provider-agnostic: run it wherever you want.

Kubernetes is a powerful tool, and is necessarily complex. Before we get into an overview, we need to introduce some terms used within Kubernetes. Containers run single applications, as discussed above, and are grouped into pods. A pod is a group of closely linked containers that are deployed together on the same host and share some resources. The containers within a pod work as a team: theyll perform related functions, such as an application container and a logging container with specific settings for the application.

Four key Kubernetes components are the API Server, the Scheduler, the Controller Manager and a distributed configuration database called etcd. The API Server is at the heart of Kubernetes, and acts as the primary endpoint for all management requests. These may be generated by a variety of sources including other Kubernetes components, such as the scheduler, administrators via command-line or web-based dashboards, and containerised applications themselves. It validates requests and updates data stored in etcd.

The Scheduler determines which nodes the various pods will run on, taking into account constraints such as resource requirements, any hardware or software constraints, workload, deadlines and more.

The Controller Manager monitors the state of the cluster, and will try to start or stop pods as necessarily, via the API Server, to bring the cluster to the desired state. It also manages some internal connections and security features.

Each node runs a Kubelet process, which communicates with the API server and manages containers generally using Docker and Kube-Proxy, which handles network proxying and load balancing within the cluster.

The etcd distributed database system derives its name from the /etc folder on Linux systems, which is used to hold system configuration information, plus the suffix d, often used to denote a daemon process. The goals of etcd are to store key-value data in a distributed, consistent and fault-tolerant way.

The API server keeps all its state data in etcd and can run many instances concurrently. The scheduler and controller manager can only have one active instance but uses a lease system to determine which running instance is the master. All this means that Kubernetes can run as a Highly Available system with no single points of failure.

So how do we use those components in practice? What follows is an example of setting up a WordPress website using Kubernetes. If you wanted to do this for real, then youd probably use a predefined recipe called a helm chart. They are available for a number of common applications, but here well look at some of the steps necessary to get a WordPress site up and running on Kubernetes.

The first task is to define a password for MySQL:

kubectl will talk to the API Server, which will validate the command and then store the password in etcd. Our services are defined in YAML files, and now we need some persistent storage for the MySQL database.

The specification should be mostly self-explanatory. The name and labels fields are used to refer to this storage from other parts of Kubernetes, in this case our WordPress container.

Once weve defined the storage, we can define a MySQL instance, pointing it to the predefined storage. Thats followed by defining the database itself. We give that database a name and label for easy reference within Kubernetes.

Now we need another container to run WordPress. Part of the container deployment specification is:

The strategy type Recreate means that if any of the code comprising the application changes, then running instances will be deleted and recreated. Other options include being able to cycle new instances in and removing existing instances, one by one, enabling the service to continue running during deployment of an update. Finally, we declare a service for WordPress itself, comprising the PHP code and Apache. Part of the YAML file declaring this is:

Note the last line, defining service type as LoadBalancer. That instructs Kubernetes to make the service available outside of Kubernetes. Without that line, this would merely be an internal Kubernetes only service. And thats it. Kubernetes will now use those YAML files as a declaration of what is required, and will set up pods, connections, storage and so on as required to get the cluster into the desired state.

This has necessarily been only a high-level overview of Kubernetes, and many details and features of the system have been omitted. Weve glossed over autoscaling (both pods and the nodes that make up a cluster), cron jobs (starting containers according to a schedule), Ingress (HTTP load balancing, rewriting and SSL offloading), RBAC (role-based access controls), network policies (firewalling), and much more. Kubernetes is extremely flexible and extremely powerful: for any new IT infrastructure, it must be a serious contender.

If youre not familiar with Docker start here: https://docs.docker.com/get-started.

Theres an interactive, tutorial on deploying and scaling an app here: https://kubernetes.io/docs/tutorials/kubernetes-basics.

And see https://kubernetes.io/docs/setup/scratch for how to build a cluster.

You can play with a free Kubernetes cluster at https://tryk8s.com.

Finally, you can pore over a long, technical paper with an excellent overview of Googles use of Borg and how that influenced the design of Kubernetes here: https://storage.googleapis.com/pub-tools-public-publication-data/pdf/43438.pdf.

Find out more about Tiger Computing.

(Image credit: Future)

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Kubernetes - taming the cloud - TechRadar

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What is NAS?

NAS is essentially a bunch of hard drives that connects to your home network, powered and housed by a small computer, enabling a centralised file storage system you can access from anywhere.

Traditionally a NAS box required a bit of know-how to get running, but manufacturers have made great strides in this area to the point that almost anyone can set up a powerful network storage solution that is more capable and flexible than a cloud storage service.

Synology's DS218J is a powerful two-bay NAS box at an entry level price of around $230.

Since you're buying the NAS box and requisite hard drives outright, there's more of an upfront investment. But it works out cheaper in the long run as there are no ongoing monthly fees. Cloud storage is akin to renting a place for your data to live, whereas NAS is more like owning your own home, giving you complete control and ownership. Boxes are designed to run 24/7, but generally don't consume a lot of power.

A two-bay NAS box can be picked up from as low as $200. Filling those slots with two 1TB hard drives will set you back another $100, so in total you're looking at $300. By comparison, a Google One plan with 2TB storage will set you back $125 a year. I invested in a more expensive five bay Synology DS1019+, and filled up the hard drive slots as and when I needed more storage over time. More drive bays also give you better redundancy, as you can mirror data so you won't lose any if one or two drives fail.

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Keep in mind that NAS boxes can do more than just store and share your photos. The likes of Synology and QNAP have an extensive app ecosystem that extends the functionality well beyond the bounds of traditional network storage.

I use mine as a media server so the family can easily stream movies and music stored on the NAS to any connected smartphone, tablet, PC or streaming box, in addition to serving as a PVR for recording major sporting events on free-to-air television. I also use it to drive and monitor my home security cameras.

There are a number of companies that make NAS boxes, including QNAP, Western Digital and Seagate, but Synology's DiskStation line is far and away the best in the industry when it comes to ease of use, stability and features.

For example making your NAS accessible from outside of your home network usually involves setting up port forwarding rules or other complicated network settings. But Synology's QuickConnect feature bypasses this by allowing you to assign a simple URL or ID for access.

The DS1019+ is a five-bay NAS box that supports 4K transcoding expansion bays for even more storage, at around $1000.

It's also the only NAS system that can match Google Photos in terms of smarts. Synology's Moments app, which runs on top of the company's Diskstation Manager operating system, analyses all your photos and puts them into sensible albums for you, making it much easier to find the photo you're looking for.

It uses facial recognition to group photos with similar faces, and scene recognition so you can search based on things that are in the picture.

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Unlike Google Photos, Synology does all this without ever collecting any user data or sending a single photo to the public cloud.

You can also set the app to automatically upload any new photos from your phone to your NAS.

Another strong point for NAS compared to cloud storage services is speed. Cloud services are limited by your internet speeds and the bandwidth of their servers, whereas NAS utilises the speed of your local home network which is significantly faster.

Of course it's always wise to keep a backup offsite of all your important files in case there's a fire or burglary. Synology has multiple options for doing this, backing up data stored on the NAS to a public cloud service like Google Drive, OneDrive or Dropbox.

The benefit here is that Synology will encrypt your data before it is uploaded, so your data can't be trawled and won't be compromised if the cloud service is hacked or breached.

Some NAS boxes allow you to sync an encrypted backup of your storage to the cloud.

Synology also offers its own private cloud option called Synology C2 Backup, with the basic plan costing between $16 and $100 a year depending on your needs.

Another option is to invest in a secondary Synology NAS offsite and have files synchronise over the internet. I personally go the manual route; plugging a USB drive into the NAS on a monthly basis to back up my most precious data, namely my collection of family photos and videos.

Krishan is a multi-award-winning Australian technology journalist.

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How to ditch the cloud and move to do-it-yourself NAS instead - The Age

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