Published on April 26th, 2022
XenServer (Currently Citrix Hypervisor) has been one of the top choices of many enterprise-grade IT admins who want to keep their primary production IT systems always up-to-date with higher flexibility and efficiency given by the popular technology named virtualisation.
Whether you’ve already an old XenServer player or a starter who want to stretch greater potentials of your IT systems on this virtual platform, to have a right XenServer backup solution is a must.
We all know that data protection is the fundamental part for data security and business continuity, something that we cannot miss before we get to enjoy the ultimate benefits brought by XenServer.
Otherwise, repairing the damage caused by server error, mistaken operation, unexpected disaster, or ransomware attacks, will definitely bring you many headaches. In this article, we’re going to talk about some major characters a mature backup solution should have to help you better find one that suits you most.
When choosing a VM backup solution, we should evaluate its capability on both backup and recovery. These two concepts are usually bound to each other since the business and security requirement for modern IT infrastructure grows along with time, having backup alone is not enough for us to prevent ever-changing challenges in the cloud environment, after all, the final purpose of us doing backups is for the fast recovery after emergencies to minimize the possible loss.
Backup
Image-based
Modern VM backup solutions usually apply image-based backup technology for less computing resource consumption and deployment time. Compared with traditional file-based backup that requires agent installation on each guest OS for file search and extraction, image-based backup works by directly copying data to the backup repository from the image or snapshot of the guest OS, which can be seen as an agentless backup process.
Fast Incremental Backup
There’re 3 general backup strategies for virtual machine backups: Full backup, differential backup, and incremental backup. Full backup is the most basic one that backs up all data in the virtual machine each time, while the other two are often combined with regular full backup to improve storage saving results and backup speed at different extent: differential backup will copy all changed data blocks since last full backup, and incremental backup will copy only the new changed data blocks each time.
Seen from the actual work cases of many, the performance of incremental backup matters most in defining a great VM backup solution, where the well-known CBT (Changed Block Tracking) should be easily found and enabled to quickly extract changed data blocks since last backup. But a problem may raise here: CBT support may be a must-have in any backup solution for VMware VMs, but is it the same for XenServer? Not really, so you should better choose one that’s compatible enough to help you automate and simplify the CBT process.
Oh, also don’t forget that forever incremental backup is another useful feature wanted by many XenServer users who expect exceptional backup efficiency. It starts with an initial full backup, and after that, only incremental backup will be involved.
In a most ideal scenario, you should be able to customize the backup plan on demand with all the strategies we list above.
Flexible Transport Methods
Maybe you’ve had enough of traditional LAN-based backup that takes long and fails to give short backup window guarantee, that’s why the other two methods are invented to help you out.
LAN-Free transport: directly copy data from production host to the backup storage through Storage Area Network (SAN) without consuming any network traffic.
Separated backup network: Another more advanced LAN-based backup strategy but isolates from the actual production network. You can configure an independent network for fast VM backup even during the busiest working hours.
You can deploy either of them to shorten backup windows, and a good XenServer backup solution should naturally offer these extra options.
Storage-Saving
As is mentioned above, incremental backup is a storage-saving approach, but it’s just a start, more subtle data reduction work needs to be done so that we can back up valuable data blocks as much as possible. Here we can name a few.
- Deduplication: exclude duplicated data blocks since last backup to store unique data only.
- Compression: well-compress the size of backup data without breaking data integrity.
- Deleted file blocks/swap files/partition gaps exclusion: These are all unnecessary files yet can take up much space in the virtual disks. By excluding them, the size of data that really needs backup can be further reduced.
Create Extra Copies
Backup solutions that support creating extra backup copies are good assistants to help you comply with the golden rule in the world of data security: the 3-2-1 backup rule.
According to the rule, it is better to save at least 3 backup copies in 2 different storage media, with 1 copy at remote site, so besides basic on-premises VM backups, features like offsite copy and cloud backup/archive should also be involved. This makes sure your important backup is always recoverable, which shows the greatest value when your local backups are unavailable for use.
Recovery
Fast Full Restore
Full recovery of virtual machine is basic, but high full restore efficiency can still be a stand-out pro of a VM backup solution. For users who prefer incremental backups, the traditional restore process will first merge these incremental data blocks into a full backup restore point and copy it to the backup storage. This process takes time. But a more advanced solution should utilize other techniques like Virtual Full Backup to instantly map a full restore point for fast full VM restore.
Instant Restore
What is the best way to bring the interrupted business back online again? The core hidden under this issue is to reduce RTOs (Recovery Time Objective). The smaller the number is, the better the result can be. Living in the age where a minute of business downtime could easily let loose opportunities that worth millions of dollars, we surely couldn’t afford loss like this too many times. Therefore, to better catch up with the chances, important business needs to be instantly recovered after breakdown.
How can we be able to get the goal easily without trouble? A good VM backup solution should help you on that. For example, if a XenServer VM crashes, with the initial backups held in hand, the backup system should be able to instantly recover the most essential files that VM reboot requires to either the original or a new XenServer host, to let applications quickly back to working status.
File-level Restore
You don’t actually have to implement a full restore every time when something’s wrong with your virtual machines, like mistaken deletion of lightweight files, or application error after improper update or modification, which does no big harm to the whole VM.
Therefore, it’ll be more convenient, if you choose a backup solution that allows you to do independent file-level data recovery that takes shorter time to process, and has smaller influence to the whole VM working environment. You can just simply browse and select the files or folders you want within a restore point at a specific point-of-time, and roll the VM back to the normal status like nothing ever happens.
Other Notable Elements You Might Care About…
V2V (Virtual-To-Virtual Migration)
Have you ever got the need to switch existing workloads on one virtual platform to another from time to time for environment update or application compatibility testing? If so, a proper backup solution should help you simplify the migration process by recovering VM backups of the original platform to another without extra configurations needed.
Management
A good VM backup solution should be easy to understand and control. If you need extra training time just to master a software that is supposed to function as early as possible, it has lost a huge part of value since the beginning, no matter how powerful the features it offers.
Affordability
I believe we all want to build a backup plan that is both powerful and cost-effective. With a bunch of backup solutions that support XenServer in the market, it’s better to compare their licensing and pricing models that suit your budget and protection requirement most. Ideally, both license per VM and license per CPU socket should be selectable for enterprises with different IT environment scales.
Wrap Up
Your well-performed XenServer virtual machines needs solid support from a well-performed backup solution. Now you know most of the important characters that a good XenServer backup solution should have to keep your mission-critical data safe in an efficient way.
When you again dive into the diversified VM backup software market, remember to take them into considerations, and don’t forget to get a free trial first before the actual purchase!
Feature image source: stockvault
