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2023 Predictions: Data Democratization To Drive Demand For High Availability

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2023 Predictions: Data Democratization To Drive Demand For High Availability

In this video of 2023 Predictions, our VP of Global Sales and Marketing Margaret Hoagland shares her thoughts on what will happen in the industry this new year.

Hoagland predicts two trends for 2023:

  • Data democratization will drive the need for high availability. As more and more people have access to data and use it in their day-to-day business than ever before, there is a pressing need for high availability.
  • Companies will perform cloud evaluation and reassess their cloud stance. After COVID, there is a need to examine if they want to go back to an on-premise environment or move different workloads in different clouds.

This year, SIOS will continue to focus on

  • High availability, ensuring companies can set up, configure failover, and maintain their systems as cost effective as possible.
  • Cloud enablement and ease of use.
Reproduced with permission from SIOS

Understanding the Complexity of High Availability for Business-Critical Applications

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Understanding the Complexity of High Availability for Business-Critical Applications

Understanding the Complexity of High Availability for Business-Critical Applications

Minimizing downtime in systems, databases, and applications is the key to maximizing productivity. Modern organizations rely on business-critical systems, databases, and applications—such as enterprise resource planning (ERP), customer relationship management (CRM), e-commerce, financial systems, and supply chain management—to operate efficiently and deliver superior customer experiences. When a system, database, or application fails, high availability protection restores operation to keep the business up and running.

What Is High Availability?

High availability is an attribute of a system, database, or application that is designed to operate continuously and reliably for extended periods. The goal of high availability is to reduce or eliminate planned and unplanned downtime for critical applications by incorporating redundant components and other technologies to address single points of failure in a system, database, or application.

Simply stated, high availability ensures that your system, database, or application operates when and as expected: “when” refers to the percentage of time the system, database, or application must be up and running as expected—meaning that the application operates the way users expect and meets their needs in a timely manner.

IDC Model

Service-level agreements (SLAs) for high availability help ensure that key components of the IT infrastructure are operational and available during business hours. IDC has created an SLA model for high availability that defines five levels with the following uptime requirements:

• AL4 (Continuous Availability—System Fault Tolerance): No user interruption and a total maximum of no more than 5 minutes and 15 seconds of planned and unplanned downtime per year (99.999% or “five-nines” availability).
• AL3 (High Availability—Traditional Clustering): Minimal user interruption and a total maximum of no more than 52 minutes and 35 seconds of planned and unplanned downtime per year (99.99% or “four-nines” availability).
• AL2 (Recovery—Data Replication and Backup): Some user interruption and a total maximum of no more than 8 hours, 45 minutes, and 56 seconds of planned and unplanned downtime per year (99.9% or “three-nines” availability).
• AL1 (Reliability—Hot Swappable Components): All service stops and a total of 87 hours, 39 minutes, and 29 seconds of planned and unplanned downtime per year (99% or “two-nines” availability).
• AL0 (Unprotected Servers): All service stops, and no uptime SLAs are defined.

Your high availability requirements depend on the criticality of the overall system, the application, and numerous other factors, including:
• How critical the applications are to the business
• Whether customers notice an impact
• How often the applications run
• How many users are affected by downtime
• How quickly a database or application must fail over to the redundant system to avoid disruption
• How much data loss is tolerable

Five nines availability is typically reserved for applications that require continuous “stateful” operation. For business-critical applications four-nines availability is standard. Non-critical systems and applications, you may only require two-nines availability. When determining acceptable downtime, it’s important to consider:

• Unplanned downtime (that is, hardware or software failures)
• Planned downtime for routine hardware and software maintenance
• Uptime at the application and database level

Various high availability solutions can help businesses achieve their SLA objectives for different systems, databases, and applications. Although continuous availability (AL4) may seem like the most appropriate goal for business-critical deployments, it’s important to find the right balance between cost and availability. Continuous availability can also have a negative impact on downtime required for planned maintenance as the system generally has to be taken offline when application or OS updates are applied, versus high availability, which typically allows for rolling updates.

High Availability Metrics: RTO vs. RPO

In addition to uptime and availability, Recovery Time Objectives (RTOs) and Recovery Point Objectives (RPOs) are important metrics used to assess high availability (as well as disaster recovery) in a system, database, or application.

RTO is the maximum tolerable duration of any outage. Online transaction processing applications generally have the lowest RTOs, and those that are business-critical often have an RTO of only a few seconds.

RPO is the maximum amount of data loss that can be tolerated when a failure happens. For disaster recovery, a typical RPO for an application and its associated data may be 24 hours. Nightly backups ensure that any changes to data over the past 24 hours can be restored in the event of a disaster. However, for high availability applications and data, the RPO is often zero. That is, there should be no data loss under any failure scenarios.

Traditional Clustering

High availability clusters are groups of server nodes (and other components) that support business-critical applications that require minimal downtime. Clustering software lets you configure your servers as a cluster so that multiple servers can work together to provide high availability and prevent data loss. IT organizations rely on high availability clustering to eliminate single points of failure and minimize the risk of downtime and data loss.

A traditional, on-premises high availability cluster is a group of two or more server nodes connected to shared storage (typically, a storage area network, or SAN) that are configured with the same operating system, databases, and applications (see Figure 1).

Figure 1: Traditional server clustering with shared storage

One of the nodes is designated as the primary (or active) node and the other(s) are designated as secondary (or standby) nodes. If the primary node fails, clustering allows operation of a system, database, or application to automatically fail over to one or more secondary nodes and continue operating as normal with minimal disruption. Since the secondary node is connected to the same storage, operation continues with zero data loss. The benefits of this cluster architecture are reduced downtime, elimination of data loss, and protected data integrity.

However, there are many scenarios in which shared storage is not wanted. A failure in the shared storage will take all of the clusters offline, making it a single point of failure (SPoF) risk. SAN storage can also be costly and complex to own and manage. Lastly, using shared storage in the cloud can add significant, unnecessary cost and complexity. Some clouds do not offer a shared storage option at all.

As shown in Figure 2, SANless or “shared nothing” clusters are the best alternative to shared storage. In these configurations, every cluster node has its own local storage. Efficient host-based, block-level replication is used to synchronize storage on the cluster nodes, keeping them identical. In the event of a failover, secondary nodes access an identical copy of the storage used by the primary node. The benefits of this cluster architecture are elimination of a SPoF, elimination of SAN cost and complexity, ease of use and cost savings in the cloud, reduced downtime, and mitigation of data loss.

Figure 2: High availability clustering with SANless or shared-nothing storage

Design Principles

The most advanced high availability clusters incorporate the following design principles:
• They automatically and quickly fail over to a redundant system when an active component fails
• They maintain application-specific best practices during and after the failover
• They provide the ability to manually switchover and switchback to enable efficient testing and “rolling” maintenance with minimal planned downtime
• They can automatically detect failures in network, storage, OS, hardware, or application
• They prevent data loss in the event of a system failure
• They failover across geographically separated nodes for disaster recovery

High Availability Clustering

A variety of clustering software solutions are available for Windows, Linux distributions, and various hypervisors (virtual machine solutions). One group supports only a single operating system, such as the following:
• Windows Server Failover Clustering (WSFC): Provides high availability and disaster recovery for hosted applications such as Microsoft SQL Server and Microsoft Exchange
• SUSE Linux Enterprise High Availability Extension (HAE): Supports clustering of physical and virtual Linux servers with policy-driven clustering and continuous data replication
• Red Hat Pacemaker (Pacemaker): Creates single-site clusters for performance, high availability, load balancing, and scalability

None of the solutions listed here can protect SAP running on Oracle Linux operating system for example. Thus, each solution limits your flexibility and deployment options. More advanced high availability solutions, such as SIOS Protection Suite for Linux, provide application-aware protection in major Linux distributions, including Oracle Linux, Red Hat, and SUSE.

In addition, every application, database, and ERP system has its own requirements for configuration and ongoing management. To meet these requirements, HAE and Pacemaker typically require a high degree of technical skill, and complicated manual scripting, which introduces the likelihood of human error and unreliable failover.

Some examples of business-critical applications, databases, and ERP systems commonly protected with failover clustering include SAP S/4HANA, SQL Server, and other applications and databases.

SAP S/4HANA

Several Linux vendors offer open source high availability extensions for SAP in their “Enterprise for SAP” subscriptions. SAP S/4HANA environments comprise multiple services such as ABAP SAP Central Service (ASCS), Evaluated Receipt Settlement (ERS), and other SAP components, that need to be maintained in the right locations and started up in the right order. In open source clustering products, such as SUSE HAE and Red Hat Pacemaker, manually configuring and managing clusters in these complex environments can be time-consuming and prone to human errors that increase the risk of catastrophic downtime and data loss.

Specific deep expertise in the applications and database is also required to create an application-aware high availability solution. In contrast, SIOS Protection Suite for Linux includes application recovery kits for SAP and HANA that ensure failovers maintain application best practices.

SAP also offers HANA System Replication, a feature that comes with the HANA software. It provides continuous synchronization of an SAP HANA database to a secondary location in the same data center, at a remote site, or in the cloud. The data is replicated to the secondary site and preloaded into memory. When a failure occurs, the secondary site takes over without a database restart, which helps to reduce the RTO. However, failback to the primary node must be manually triggered. HSR needs to be paired with an application-aware clustering software such as SIOS Protection Suite that can detect failures and orchestrate failovers if necessary.

SQL Server

Many companies rely on SQL Server as the back-end database for key applications supporting important business functions. Microsoft WSFC is commonly used to support Always On Availability Groups (AG) and SQL Server Failover Cluster Instances (FCI) for SQL Server applications.

However, WSFC with AG requires costly SQL Server Enterprise Edition licensing. In addition, With FCI, the entire instance is failed over to the standby node. With AG only the databases in the group are protected.
Using SIOS DataKeeper with WSFC allows you to provide advanced high availability protection for SQL Server using cost-efficient Standard Edition licensing.

Other Applications and Databases

SIOS software can be used to protect a wide range of business-critical applications, databases and ERPs, including Oracle, MaxDB, MySQL, PostgreSQL, and DB2. SIOS software enables clustering and disaster recovery.

In our next blog, we’ll take a look at specific industry use cases to help you understand how different businesses achieve high-availability for their mission-critical applications.

Reproduced with permission from SIOS

Video: How SIOS Ensures High Availability For The Financial Services Industry

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Video: How SIOS Ensures High Availability For The Financial Services Industry

In this ongoing series about high availability (HA) and disaster recovery (DR) for various industries, Greg Tucker, Senior Product (Windows) Support Engineer at SIOS Technology,  joins us to share his insights about how the company protects the financial industry from downtime and failover.

SIOS has a global presence in the financial industry with customers ranging from commercial banking, various brokerage firms, wealth management, CPA firms and so on. No other industry is more mission-critical and sensitive to downtime and failure than the financial industry,  with customers relying on critical applications for their online banking systems, ATMs, and payment systems. “We provide failure or clustering software that will protect their critical applications and data from downtime and/or a catastrophic event,” says Tucker.

Tucker explains that in essence, the critical applications are deployed on a primary server, whether it be on-prem or in the cloud, as it is clustered with a secondary server or multiple servers. “In the event, the clustering software detects a failure, it will move all the resources over to the secondary node and restore services to the end users automatically; no data loss, no disruption,” he adds.

Check out the whole interview above to learn more.

Highlights of the discussion:

  • SIOS has a global presence in the financial industry with customers using SIOS products to eliminate a single point of failure in their cluster environment.
  • With a shift towards cloud, there is a business requirement (SLAs) to protect and make data highly available for Oracle, SAP, SQL, SAP MAxDB, file shares and generic (legacy) applications.
  • Scalability that comes with cloud can pose some challenges to high availability but SIOS clustering solution designed for cloud can swiftly handle those potential challenges.
  • Tucker addresses some common misconceptions about high availability, especially in the financial service industry.
  • Importance of HA for financial institutions.

Solutions

Connect with Greg Tucker (LinkedIn)

Reproduced with permission from SIOS

SIOS Technology Helps Telcos Navigate the Complexities of High Availability

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SIOS Technology Helps Telcos Navigate the Complexities of High Availability

In today’s connected world, high availability is not only essential — it is considered a lifeline of society and the economy. No internet means no cloud. Just a few minutes of downtime can cost companies millions of dollars and damage customer relationships. While cloud computing, edge computing, and IoT present many opportunities, they are also challenging to navigate.

In this ongoing series about high availability (HA) and disaster recovery (DR) for various industries, Harry Aujla, EMEA Pre-Sales Director of SIOS Technology Corp., discusses the importance of high availability in the telecom sector. He points out the challenges telcos are currently facing with high availability and how SIOS Technology is helping.

Check out the whole interview above to learn more.

Key highlights from this video interview:

  • The telecom sector is unique because it has a direct impact on most aspects of our professional and personal lives. We live in an interconnected society, so even if critical communication services are down for just a few minutes, it can cause havoc and lead to millions of dollars in lost revenue.
  • Telecom is constantly innovating and evolving with technologies such as 5G rollouts and cloud computing. Maintaining uptime and having high availability remain critical for customer facing systems and backend systems.
  • Aujla discusses how software-defined systems and decentralization are solving some of the challenges telcos face, particularly when considering agility and reliability.
  • Continuity is essential in the telco market, particularly since they deal with infrastructure critical systems, which are often protected with a fault tolerance solution. Aujla tells us that that means telcos often have an SLA of 99.99% availability (or five minutes of downtime per year).
  • Software-defined systems have enabled telcos to embrace digital transformation into the cloud, and to leverage the cost and flexibility that comes with cloud computing.
  • For VoIP systems, the cloud platform provider will only provide high availability services to a certain level within the solution stack, and the responsibility of maintaining SLAs within the cloud falls on VoIP providers and customers. Aujla explains how this is addressed by high availability tools.
  • For telcos, billing systems are considered critical. If customers cannot view or pay their bills, it will cause disruption for all parties involved, potentially affecting revenue and customer satisfaction. SIOS aims to deliver application availability and 99.99% SLAs.
  • IoT is a key use case of cloud computing, with data-capturing devices constantly feeding back into a central brain. Aujla explains why it makes sense to leverage the flexibility and agility cloud platforms offer.
  • Endpoints of IoT devices typically do not need high availability, but rather the data itself. However, the volume of data being collected today presents numerous challenges on the underlying infrastructure in terms of servers, storage, and networking. Aujla explains how this is driving cloud consumption and edge computing.
  • Cloud providers are geared towards availability of the infrastructure itself rather than monitoring what is happening inside the cloud instance where the IoT-centric applications could be running. For this reason, Aujla feels that it is up to customers to take responsibility for their application availability in the cloud.
  • SIOS has the ability to cluster and monitor applications and databases in the cloud, and should it detect failures, it can failover to the next available node in the cluster. Aujla explains how this improves the overall high availability SLA for protected applications.

Solutions

Connect with Harry Aujla (LinkedIn)

Reproduced with permission from SIOS

The simple days of HA & DR are gone

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The simple days of HA & DR are gone

Flipping through the TV channels I stumbled on the scene in the movie “He’s Just Not That Into You” with Drew Barrymore, saying what most of us in 2022 are feeling about Technology and especially high availability and disaster recovery:

“I miss the days when you had one phone number and one answering machine and that one answering machine had one cassette tape and that one cassette tape either had a message from a guy or it didn’t. And now you just have to go around checking all these different portals just to get rejected by seven different technologies. It’s exhausting.”

Sometimes, don’t you wish there was only one cloud or maybe even no cloud platform; one DB running on one OS; and only a front end application to worry about. But, the world has changed and is moving faster, and becoming more complicated.  Advances in technology, the fallout of mergers and acquisitions, and the increasing appetites and pace of our 24/7 society, with billions of consumers looking for the latest deal and the best experience, means that the simple days are gone.

4 hard truths about your availability

  1. Your solution isn’t as simple as you think

Of course your enterprise environment isn’t simple.  You have legacy systems and applications, the kind that have been around almost since punch cards.  You have new systems, made for the new generation of applications and databases.  In addition you have solutions that were created a decade ago to bridge the gap or span the time between migrating from one platform to another, but despite your best efforts, these systems linger. Added to these challenges is a growing set of systems and IT resources from the merger and acquisition of Company U.  Delivering HA is not as simple as you think in the new era.

  1. Bad architecture is a bigger problem than you realize

As VP of Customer Experience, we’ve seen the damage caused by bad architecture.  While deploying HA software can definitely help improve an application and database’s availability, HA software will never fully overcome incomplete requirements, poor networking, lack of redundant hardware, or other missing architectural components.  Our team once worked with a customer to correct an undersized environment that left their system unstable during peak operating times.  Because of their bad architecture, which included networking and hardware instability, their teams frequently found themselves scrambling to recover from avoidable downtime issues.  In order to have a complete and sound, highly available and resilient solution you will need to deploy great software as a part of a sound architecture.

  1. Your admins need more help than they’ll admit

Developing an enterprise grade, highly available resilient HA solution, built on a solid architecture with the ability to grow is not a simple process.  Designing and architecting for resilience, application and data availability is not as easy as grabbing a box of cake mix off the shelf.  Throw in an array of tools, processes from different teams, a mixture of SLA’s, and the varieties of OS, applications, databases, and platforms and you have a recipe for needing help.   Recently, I interviewed a 20 year veteran working in an enterprise support environment.  He described how many of his peers, and even at times himself, have not been able to handle the weight of maintaining critical enterprise availability.  Your admins, not only need help when they have been up since 2am dealing with a catastrophic, multi-system, multi-application, nearly complete data center collapse, but also in the day to day hard work of enterprise availability in one of the most technologically complex eras ever.

  1. Your solution may not be as highly available as you think 

“While public cloud providers typically guarantee some level of availability in their service level agreements, those SLAs only apply to the cloud hardware.” There are many other reasons for application downtime that aren’t covered by cloud provider SLAs including:

  • Software issues and bugs
  • Human errors
  • Software failure
  • System or application hangs

As VP of Customer Experience we’ve seen a thing or two, including a denial of service attack caused by a failed exit in a recursion routine, system exhaustion, security software quarantine of healthy, critical applications, kernel panics, and virtual machines that randomly reboot.  If your HA strategy is relying solely on the SLAs of your hypervisor, your solution may not be as highly available as you think. You need to protect critical applications with clustering software that can monitor and detect issues, respond to problems reliably, and if necessary move operations to a standby server to ensure that your products and services remain reliable and available when and where they are needed.

Our single data center has become a series of cloud platforms, spanning dozens of data centers.  Our skunk work application has become a part of the bevy of critical front end, middleware and backend solutions that we must manage across Windows, Linux, and a few different *Nix varieties.  The march of technology means that our high availability has become more complex and requires better architecture.  It also means that our teams need more help to manage it all, and if we aren’t careful it could mean that we remain vulnerable and exposed.  Which of the four truths is your team facing most?

Cassius Rhue, VP Customer Experience

Reproduced with permission from SIOS