MAKING YOUR VIRTUAL INFRASTUCTURE NON-STOP Making availability efficient with Veritas products

Transcription

1 TECHNOLOGY REVIEW MAKING YOUR VIRTUAL INFRASTUCTURE NON-STOP Making availability efficient with Veritas products AUGUST 2015 All businesses have a core set of applications and services that are critical to their ongoing operation and growth. They are the lifeblood of a business. Many of these applications and services are run in virtual machines (VM), as over the last decade virtualization has become the de facto standard in the datacenter for the deployment of applications and services. Some applications and services are classified as business critical. These business critical applications require a higher level of resilience and protection to minimize the impact on a business s operation if they become inoperable. The ability to quickly recover from an application outage has become imperative in today s datacenter. There are various methods that offer different levels of protection to maintain application uptime. These methods range from minimizing the downtime at the application level to virtual machine (VM) recovery to physical system recovery. Prior to virtualization, mechanisms were in place to protect physical systems and were based on having secondary hardware and redundant storage systems. However, as noted above, today most systems have been virtualized. The market leader in virtualization, VMware, recognized the importance of availability early on and created business continuity features in vsphere such as vmotion, Storage vmotion, vsphere Replication, vcenter Site Recovery Manager (SRM), vsphere High Availability (HA) and vsphere Fault Tolerance (FT). These features have indeed increased the uptime of applications in the enterprise, yet they are oriented toward protecting the VM. The challenge, as many enterprises have discovered, is that protecting the VM alone does not guarantee uptime for applications and services. Detecting and remediating VM failure falls short of what is truly vital, detecting and remediating application and service failures. With application and service availability in mind, companies such as Veritas have come in to provide availability and resiliency for them. Focusing on improving how VMware can deliver application availability, Veritas Technologies LLC. has developed a set of solutions to meet the high availability and disaster recovery requirements of business critical applications. These solutions include Veritas ApplicationHA (developed in partnership with VMware) and Veritas InfoScale Availability (formerly Veritas Cluster Server). Both of these products have been enhanced to work in a VMware-based virtual infrastructure environment. Copyright Taneja Group, Inc All Rights Reserved. 1 of 7

2 Veritas ApplicationHA ApplicationHA is an application availability software solution that integrates with vsphere HA to enhance application recoverability. It does this by providing a layer of application intelligence that is lacking in vsphere. This intelligence provides additional application resiliency. To accomplish this ApplicationHA uses an Intelligent Monitoring Framework (IMF) to extend application monitoring beyond the traditional approaches of application polling and port checking. IMF uses an agent in the VM to detect events and application faults. The agent integrates into both the operating system and application. VMware vsphere AppHA Sunset Announcement VMware included a feature called vsphere AppHA with the release of vsphere 5.5. It was rather limited as it only provided high availability for six different middleware applications. Configuration of ApplicationHA is relatively simple as it automatically discovers an applications components. Once these components are discovered, the user confirms the configuration with just a few mouse clicks. The management of ApplicationHA is incorporated into the vsphere management framework by leveraging the ApplicationHA vsphere plugin. The plugin can be used with both the vsphere Web Client (Figure 1) and the vcenter Windows client (Figure 2). With the release of vsphere 6.0 VMware announced that vsphere AppHA would be removed as a feature and there would not be a replacement for it. VMware recommends using a supported 3rd party product to replace it. Figure 1 Copyright Taneja Group, Inc All Rights Reserved. 2 of 7

3 Figure 2 VMware s vsphere HA can detect both individual VM and entire ESXi host failures. VM failures typically result from a fault at either the operating system or storage level. If such failures are detected, vsphere HA will restart the VM on the same host or, if needed on another host. ApplicationHA improves on vsphere HA by detecting failure at the application level. If ApplicationHA detects that an application has failed it will attempt to restart it using various methods (Figure 3). As a last resort, if the application cannot be restarted it will trigger vsphere HA to reset the VM. Figure 3 Veritas InfoScale Availability (formerly Veritas Cluster Server) Enterprises may have some applications that require increased service level agreements (SLAs). Consequently they will need a higher level of availability even beyond what vsphere HA and ApplicationHA can offer. InfoScale Availability provides the recovery time objective (RTO) to meet these increased SLAs requirements. In contrast to ApplicationHA, InfoScale Availability cannot only monitor an application for failure, but can fail the application over to a running VM on a different vsphere server. More importantly, InfoScale Availability manages the disks that contain an application s data so that it can be immediately reassigned to the standby VM. Further expanding its Copyright Taneja Group, Inc All Rights Reserved. 3 of 7

4 usefulness, InfoScale Availability supports both VMDK and RDM disks. Once a failure occurs, InfoScale Availability detaches the disks from the failed server and reattaches them to the standby server. For many applications, this failover is so rapid (30-45 seconds) that it may go unnoticed by the user. Using InfoScale Availability to control the assignment of the data disk eliminates the need to share disks between VMs. InfoScale Availability is integrated with the vsphere management UI, but more importantly commonly used vsphere capabilities are not compromised when using it. Many other clustering products on the market work in a virtual environment but they are incompatible with frequently used vsphere capabilities such as vmotion and Storage vmotion. This unique integration with vsphere is a key advantage that InfoScale Availability has over other clustering products that we have seen. InfoScale Availability is fully compatible with VMware vsphere and the vcenter Server UI can be used to manage the protected environment. Figure 4 below shows how InfoScale Availability utilizes the Veritas vcenter plugin management interface to show an application s dependences via the vcenter UI. Figure 4 Comparing vsphere HA with ApplicationHA and InfoScale Availability The most obvious benefit of ApplicationHA and InfoScale Availability over vsphere HA is that they can recognize and resolve issues at the application level. We have found vsphere HA a good choice for protecting the physical virtualization layer of a datacenter, however vsphere HA does not have the ability to go deeper in order to monitor applications and remediate against their failures. Copyright Taneja Group, Inc All Rights Reserved. 4 of 7

5 Testing Method To test and compare the performance of ApplicationHA and InfoScale Availability, we carried out a simulation of an application fault by powering down the ESXi host that was hosting a VM which was running an application. We then measured the time it took for each of the solutions to fully restore the service provided by the application. Results ApplicationHA After the ESXi host was powered down, ApplicationHA instantaneously recognized that the application was unresponsive. ApplicationHA attempted to restart the application. When that process failed, it attempted to gracefully reboot the VM. This was not possible as the VM was powered off. The next step successfully triggered vsphere HA to restart the VM on another host. In order to shut down the VM in as a graceful manner as possible and allow for a more orderly shutdown of any other applications or tools ApplicationHA can be configured to try and reboot the VM a number of times before rebooting it. Veritas recommends that ApplicationHA be configured to attempt multiple restarts before rebooting. This will ensure that the VM is shutdown in as clean of a manner as possible. Omitting this step will force vsphere HA to carry out a hard reset of the VM (the default operation of vsphere HA). This is not ideal and increases the likelihood of file corruption. InfoScale Availability After the ESXi host was powered down InfoScale Availability, like ApplicationHA also instantaneously recognized that the application was unresponsive. ApplicationHA then immediately transferred the application and its data disks to a standby VM. The recovery time was much faster than both vsphere HA and ApplicationHA, as a reboot of the VM was not required. We found that InfoScale Availability offers more extensive protection for applications and quicker recovery times. VMware vsphere HA Veritas ApplicationHA Veritas InfoScale Availability Included with ESX Additional solution Application Status vsphere Features Virtual machine restarts Application Restarts Failover to standby VM Near instant recovery Loss of VM (power off) Time for Service 4 Minutes 4 Minutes Less than a minute; application switched Copyright Taneja Group, Inc All Rights Reserved. 5 of 7

6 recovery over to standby VM Application Fault (process terminated) time to Service recovery No application fault detection Less than a minute to restart application plus OS reboot overhead when process killed a number of times. Less than a minute; application switched over to standby VM During the testing, vmotion and Storage vmotion operations were carried out in the cluster. These operations were completed without incident, demonstrating to us that these vsphere features were not compromised during testing. Summary of testing Customers can be satisfied that both Veritas High Availability solutions: ApplicationHA and InfoScale Availability can offer the level of protection businesses need in order to be successful. Both enhance the VMware technologies that companies have invested in, without compromising any of the vsphere features they use on a daily basis. Veritas InfoScale Operations Manager Another benefit of using ApplicationHA and InfoScale Availability is they both enable the use of Veritas InfoScale Operations Manager. InfoScale Operations Manager is the Veritas management interface that assists customers in managing applications across both VMware and non-vmware environments where Veritas high availability solutions are deployed. InfoScale Operations Manager allows for control of the application tier regardless of its state: physical, virtual, or a mix of the two. Multi-tier Application Recovery with ApplicationHA, InfoScale Availability and Virtual Business Services Virtual Business Services, offered through InfoScale Operations Manager, provides high availability and a complete multi-tier business service management for business-critical services which can be made up of the various tiers of heterogeneous operating systems, platforms, hardware and software. It combines the power of ApplicationHA, InfoScale Availability, and InfoScale Operations Manager. In a multi-tier business service, different tiers usually have different requirements. While one tier may require full-fledged high availability with split-second error detection and fast failover, other tiers might require only basic start and stop capability. Hence, the one size fits all approach is not applicable in most cases. Key features of Virtual Business Services include: Complete multi-tier management, such as coordinated start and stop across different operating systems and/or platforms Fault management and propagation between tiers Multi-tier Disaster Recovery support, enabling automated Disaster Recovery of a complete Virtual Business Service Virtual Machine management support (start and stop) Multi-Tenancy and Role-Based Access Control Copyright Taneja Group, Inc All Rights Reserved. 6 of 7

7 It is important to understand that high availability is primarily managed within each tier or layer. An example of this would be a three tier application where: the web tier is comprised of a web server running as a VMs on vsphere, the application tier consisting as a cluster of virtualized Linux nodes, and a database tier is running on a physical platform. Logically, a Virtual Business Service can be seen as a container that allows all the tiers of an application to be grouped into a single object for management purposes. Figure 5 below shows how these layers are grouped together and displayed on the InfoScale Operations Manager web portal. Figure 5 Taneja Group Opinion We found that both of the Veritas high availability solutions that we examined offer the extra level of protection today s dynamic businesses need in order to be successful. These products enhance VMware vsphere virtualization technologies without compromising any of the vsphere features they may be using on a daily basis. Whether a customer s SLAs require a recovery time of minutes or sub minutes, Veritas high availability solutions will provide the ability to meet their goals.. NOTICE: The information and product recommendations made by Taneja Group are based upon public information and sources and may also include personal opinions both of Taneja Group and others, all of which we believe to be accurate and reliable. However, as market conditions change and not within our control, the information and recommendations are made without warranty of any kind. All product names used and mentioned herein are the trademarks of their respective owners. Taneja Group, Inc. assumes no responsibility or liability for any damages whatsoever (including incidental, consequential or otherwise), caused by your use of, or reliance upon, the information and recommendations presented herein, nor for any inadvertent errors that may appear in this document. Copyright Taneja Group, Inc All Rights Reserved. 7 of 7