Glossary of Terms

Optimizing and Protecting Business-Critical Application Environments

Application Monitoring  Tools designed to ensure software applications perform as expected. IT professionals use APM tools to ensure their end-users get the quality of service they expect from important business applications. In virtual environments, application monitoring tools helps administrators ensure that application servers operate within the parameters of their service-level agreements (SLAs).  
Application Performance Management (APM)The software and processes IT professionals use to monitoring and managing the performance and availability of software applications.  
Backup Backup is a standard IT business practice of making and retaining copies of important data and storing these copies in a location that is geographically distant from the production environment where they originated. Backup ensures that important data will not be lost if the primary system goes down or is damaged.  
Cloud Cost Optimization  Cloud cost optimization is the process of analyzing and assigning cloud computing resources, including compute, storage, and networking to an application, infrastructure, or workload according to utilization requirements. Allocations may change over time according to situational, daily, weekly or seasonal utilization requirements.  
Cloud Migration  Cloud migration is the process of moving application environments and data, from on-premises data centers into a cloud-based infrastructure.This process requires detailed planning to ensure that the application environment in the cloud meets expectations for operational efficiency and availability protection.  
Clustering Software  Software that enables IT to configure a group of servers to work together. If the software detects that one of the servers, or nodes fails or that the application running on the server is no longer accessible by end users, it moves the application operation to another node in the cluster. Windows Server Failover ClusteringSIOS Protection Suite are examples of Clustering Software.  
Data Replication  The practices of copying information between redundant servers and keeping the copies consistent to improve reliability, fault-tolerance, or accessibility  
Database Replication  The practice of copying data from a database in one computer or server to a database in another to create a distributed database in which multiple users can access data at once. SIOS Datakeeper provides host-level, block level replication.  
Disaster Recovery  Provides a structured approach for responding to unplanned incidents that threaten a company’s IT infrastructure. Disaster recovery protection typically involves ensuring redundancy and geographic separation of business-critical operations, data, and systems.    
Disaster Recovery Software  In the event that a sitewide disaster or serious human error damages business-critical technology systems or infrastructure, disaster recovery procedures restore operation of business-critical applications and processes. Disaster recovery software replicates or moves important data and applications to a location that is geographically separated from the production location so that,in the event of a sitewide or regional disaster, it can be restored. Learn more about Disaster Recovery.  
Failover Cluster  A failover cluster is a group of servers that are configured to work together such that if one of the servers, or nodes, fails, another node in the cluster can take over operation of its application without any downtime to deliver high availability.  
Fault Tolerance  Fault tolerance is a level of protection in a computing environment used for mission-critical applications that require >99.999% availability and RTO and RPO of near zero. Fault tolerant systems require an investment in redundant hardware, software, networking and other systems. In these environments, two or more systems operate synchronously – performing compute functions simultaneously, so that in the event of a hardware, software, or network failure, application operation will continue without interruption or dropped transactions.  
Geoclustering  Geoclustering is the practice of geographically separating high availability cluster nodes for disaster recovery protection. In a high availability cluster, important applications are run on a primary server node that is connected to one or more secondary nodes in a cluster. If application operation fails on the primary node, cluster software orchestrates failover of the application operation to the secondary node (s). If the primary and secondary nodes are located in the same geographical location, any risks to that location (eg. fire, flood, natural disaster) threatens the entire cluster. By locating cluster nodes in multiple different physical locations, a geocluster enables application operation to continue through local downtime incidents and natural disasters.
High Availability  A system or application that is continuously operational. Availability can be measured in terms of percentage of uptime relative to 100% uptime (operational). An application or server said to have “five 9s” high availability has 99.999 percent uptime.  
Infrastructure Monitoring  IT infrastructure monitoring connects data from a wide variety of IT devices and applications to ensure IT infrastructure is running within optimal parameters.  
IT Analytics  IT infrastructure refers to the analysis of data from the hardware, software, network, storage, application and compute resources. IT professionals use IT analytics to ensure their infrastructure is optimized, Service Level Agreements are met and that application performance is maintained for end users.  
Linux Clustering  With Linux clustering, an application is run on one node, and clustering software is used to monitor its operation. If the software detects an issue, it moves operation of the application to the secondary node in a process called failover.  
Oracle Clustering  Oracle clustering is a way of providing high availability protection for the application by eliminating single points of failure by running the same operating system and databases and applications on multiple servers all of which share the same storage or connect to storage that is continuously synchronized.  
Quick Starts  Quick Starts are templates or shortcuts created by public cloud solutions architects and software application vendors that  automate and simplify the process of deploying an application environment in the cloud quickly and easily.  
Recovery Database  A recovery database (RDB) is a function in some email systems that facilitate recovery in the event of a failure. RDB enables email system administrators to mount and extract data from a restored mailbox database as part of a recovery operation in order to recover data from a backup or copy of a database without disrupting user access to current data.  
SAN Storage  SAN stands for storage area network. SANs is a network of storage devices shared by servers. It provides block-level storage that can be accessed by the applications running on any networked servers. Traditional failover clusters require shared storage (typically SAN) so that in the event of a failover the secondary cluster node has access to the same, up-to-date data as the primary node.  
SAP Clustering  SAP clustering allows your organization to automatically fail over application operation to one or more secondary nodes, mitigating downtime, eliminating data loss, and maintaining data integrity.  
SQL Failover  When clustering software detects a failure in the primary cluster node, it moves operation of the SQL Server to the secondary node in the cluster in a process called failover. Since the secondary node has access to the same data as the primary node, operation continues without downtime or data loss.  
SQL Server Clustering  Clustering SQL servers provides high availability and protection from disasters whenever a server hosting the SQL Server instance fails.  
Stateful applicationsStateful applications, such as online order forms or email transactions track and store information about the state of application during user session with that application, such as window location, setting preferences, and recent activity. They enable users to begin a session and then return to it later and pick up where they left off. When the user returns to the application, it responds with the context of all of the previous transactions/action performed by the user in the past. It is important to note that stateful applications use the same servers each time they process a request from a user and store the state information on that server. For this reason, stateful applications are more difficult to scale and less innately resilient than stateless applications. Stateful applications may require more complex mechanisms for load balancing and session management.
Stateless applicationsStateless applications provide one service or function and use a web, or print servers to process short-term requests. Each user interaction with a stateless application is as if the user was using it for the first time. It treats each request as an independent, isolated transaction. Nothing about the user’s previous usage is storage. One example of a stateless application is a simple calculator app or website. When you use a calculator to perform a calculation, each operation is independent of any previous calculations. The calculator doesn’t retain any memory of past calculations or user interactions once the calculation is complete. Each time you perform a new calculation, it’s as if you’re using the calculator for the first time, without any context or history retained. Therefore, calculator applications can be considered stateless as they don’t maintain any state or memory of previous interactions with the user.
System Restore  Similar to system recovery, system restore is the process of returning a computer system to an operating state by restoring files from hard disk and restoring registry, system memory and storage media. Microsoft Windows Server environments System Restore feature can return a system operation using snapshots of some system settings, allowing you to revert to specific files and settings without reinstalling the entire operating system.  
System Recovery  In computing, system recovery refers to the process of rebuilding a computer system or restoring data from a secondary source, such as an external hard drive. Because this process can require extended application downtime, mission-critical applications are typically protected with high availability clustering that automatically moves application operation to a different server until the primary system can be fully recovered or replaced.  
Virtual Machines  A virtual server or virtual machine (VM) is a software based computer architecture that emulates the user experience of a hardware based server. VMs allow the user to run multiple operating systems on the same physical machine. They allow users to allocate critical resources such as compute, storage, networking as needed without the constraints of physical servers.  
Windows Server Failover Clustering (WSFC)  A (WSFC) cluster is a group of independent servers that work together to increase the availability of applications and services. SQL Server 2017 takes advantage of WSFC services and capabilities to support Always On availability groups and SQL Server Failover Cluster Instances. SIOS DataKeeper is integrated with WSFC adding the configuration flexibility to build WSFC clusters in the cloud.