VM Backup Reference Architecture – Part 2: Beyond VADP
UPDATE: Some good information in the comments. I will be posting follow-up updates on both Veeam and Vizioncore solutions either during or after VMworld.
In Part One, I discussed the features provided in VMware’s VADP (vSphere API for Data Protection). Most major backup vendors offer support for VADP, and some of them also support CBT, which can provide very significant reductions in both backup windows and disk I/O.
Several backup vendors offer additional capabilities in a virtualized environment but first a quick look at VADP from a different perspective. Below is a graphic from Vizioncore which describes what they call Backup 2.0:
This graphic illustrates that there are very significant costs and complexities related to traditional agent-based backup. By leveraging VADP, organizations can capture significant ROIs and efficiencies using image-level backups, source de-duplication, and single step restores. For the purposes of this article I don’t want to drill to deep here, but you can read more about Backup 2.0 here.
Vizioncore (Quest) and Veeam are two backup vendors that offer significant additional benefits in virtual environments. Rather than retro-fitting a Backup 1.0 solution to work with Backup 2.0, these two vendors have developed Backup 2.0 solutions from the ground up, and are primarily focused on virtualized environments.
According to IDC, Vizioncore (Quest) is the 3rd largest management software vendor for virtualized environments behind VMware and Microsoft, while according to Gartner, Quest/Vizioncore is one of the top 10 enterprise backup vendors and is the fastest growing among all of them.
Before I continue a quick disclaimer. I use and have significant experience with Vizioncore’s products. I have not yet had the opportunity to work with Veeam’s products but from what I understand they also provide very strong solutions which are worthy of consideration.
Replication, Backup and CDP
Both Vizioncore and Veeam will be demonstrating version 5 of their backup and replication products at VMWorld in less than 2 weeks. In Vizioncore’s vRanger 5.0, the backup and replication products will be integrated and will share a common engine. This is already the case in Veeam’s Backup and Replication 4.1.
Integrating replication and backup enables an agentless CDP (Continuous Data Protection) capability which can be much more cost-effective than traditional agent-based CDP solutions. Veeam supports “Near-CDP” today in their Backup and Replication 4.1 product, while Vizioncore (Quest) is expected to be adding the same in a 5.0 release due early next year.
VSS and Disaster Recovery
Both Veeam and Vizioncore offer their own VSS agents to overcome application consistency issues which I discussed in an earlier post. They both also offer integration with de-duplication solutions like EMC’s Data Domain or inline compression such as Nimble Storage for effective disaster recovery.
Solutions like Data Domain and Nimble Storage are an excellent way to provide disaster recovery — your backups are copied to disk in the primary site, and then the de-duped differences are replicated in a WAN-efficient manner to a like device in your DR site.
Many backup solutions will require some form of a proxy server, to handle the “data moving”. The problem with this is scalability. A data mover will only be able to move a certain volume of GB/hr before it becomes saturated. This problem can be solved by adding more hardware, but this will increase your capital and operational costs.
Vizioncore’s vRanger 4.5 uses a Direct-To-Target architecture which solves this problem by eliminating the proxy server. In this model the image is compressed at the source (ESX host) and then written directly to the backup target. The backup model here is parallel rather than sequential. Multiple jobs are running at the same time on the same host, and across multiple hosts.
According to tests observed by Vizioncore, this allows for backups that are 3-4 times faster for LAN backups, and a 1.75 times faster for LAN-free backups. These results were obtained comparing with two other backup solutions –each of them supporting CBT – in an environment with only 3 ESX hosts.
Direct-to-Target is not supported for ESXi hosts at this time, however this support is planned for vRanger 5.0 early next year.
Active Block Mapping (ABM)
This is a patented technology used in Vizioncore’s vRanger product to reduce the amount of data that needs to be backed up.
When a file is deleted in the NTFS file system, the entry is removed from the directory table but the actual file remains on the actual disk blocks until those blocks are overwritten. ABM will query the NTFS file system to determine which blocks are used by active files, allowing it to skip disk blocks that are not actively in use.
Both Vizioncore and Veeam will be introducing an instant restore functionality in each of their upcoming 5.0 products. The idea here is that the VM can be run directly from the backup respository, while a storage vMotion attempts to move the VMDK’s to production-class storage in the background.
Needless to say, this is potentially game changing. The idea of an instant restore for most servers was a fantasy until recently. This can significantly reduce risk (and lost revenue) by nearly eliminating RTO latency following a server being impaired and requiring a restore.
VADP offers many benefits including CBT that many backup vendors can take advantage of. However there are technologies that go beyond VADP that can provide significant value to the enterprise from backup vendors like Vizioncore and Veeam which include:
- Near-CDP (Veeam 4.x, vRanger 5.0)
- Enhanced VSS and DR integration (Veeam, vRanger)
- Direct-To-Target (vRanger 4.5)
- Active Block Mapping (vRanger 4.5)
- Instant Restores (Veeam 5.0, vRanger 5.0)
- Object-Level Restore for Exchange (vRanger 4.5)