Data Backup and Redundancy

IT systems are now so complex and data volumes so large that achieving reliable database backup and redundancy can be a big challenge for many companies. Users are more mobile, and the number of different systems used within organisations is increasing. With up to 50% growth year on year, the result is that many backup systems are struggling to cope. At the same time, achieving high levels of redundancy can be expensive and companies risk paying a premium for high-spec solutions that far outperform their needs.

Blueberry Consultants understands that every customer is different, both in terms of architecture and budget. We look at everything from simple off-the-shelf tools to solutions that are custom fit to your systems – with a constant focus on increasing capacity and reducing costs. With strong expertise in Linux system configuration, Cisco firewall administration, SQL Server management, VMware administration and Windows development, we have the technical skills to get the maximum benefit from even the most complex customer infrastructure. This wide range of skills is concentrated in a tight-knit team, allowing us to work with any customer infrastructure and design effective backup strategies for even the most complex systems.

Cloud-based services such as Amazon’s EC2 offer a cost-efficient and scalable option for offsite backup. Users can easily access data remotely and businesses can expand their storage requirements as needed. There are still some issues to consider when choosing a solution. Pricing models vary from provider to provider, ranging from tiered pay-as-you-go options to basic flat fees. Some vendors may also charge for additional backup services. Sufficient bandwidth is a crucial consideration, although many providers will only send changed data over the network after the first full backup. Data security is also a valid concern and Service Level Agreements (SLA) should be carefully scrutinized to ensure the proper measures are in place.

The same is true for all backup offerings, particularly when delivered as part of a package by hosting companies or Internet Service Providers. It pays to find out exactly the level of backup on offer. SLAs should stipulate specific levels of data availability and set timeframes for recovery.

Live data presents a number of challenges for database backup, particularly in the case of database files that are continuously being written to. Ensuring no changes are lost in the backup process can require considerable configuration. Blueberry can apply a number of optimization techniques to ensure continuous backup of live data.

Backing up Web or database servers can also be tricky. Traditionally, a list of folders is written to backup but this leaves data open to human error. A full backup is the failsafe option but with storage space at a premium, solutions that combine one full backup with subsequent incremental backups offer a cost-efficient alternative. One example is the incremental snapshot system provided with the Cloud-based Amazon EBS service.

Backing up in virtual environments demands a different approach from physical servers. The critical factors are storage availability, configuration and management. If these are properly addressed, the benefits can be considerable. Blueberry has experience in engineering unusual backup systems in virtual environments and mirroring virtual machines from one server to another.

Achieving high levels of redundancy usually requires two servers. This can be costly and companies should consider whether instant redundancy is really vital for their business. With solutions such as Amazon EBS, for example, a new system can be set up from a snapshot in just 30 minutes without the need for two servers. Redundancy of database servers is more complex to configure and usually requires some level of mirroring or replication. Blueberry Consultants leverages a range of tools and techniques to optimize this process. These include custom compression, encryption, data deduplication and incremental transfer approaches.

Testing is often the missing link in database backup strategies. The time and money invested in backing up data is too great to risk your recovery plan failing at the critical moment. Companies should schedule regular testing of their backup and restore processes. Cloud setups offer the most convenient test environment with the capacity to restore to a second server instance temporarily. Backup reporting tools can also help safeguard your data by tracking backup failures and determining their causes.

These reporting tools look at the whole data protection lifecycle. This type of holistic approach is perhaps the key to optimising backup on an ongoing basis. The big picture is critical. You need to know your business, know your provider and know your limits in terms of budget, bandwidth and storage space before you go looking for a solution. This not only means analysing your data volumes and usage, but also assessing how well your current backup tools are aligned with your business priorities. And don’t let technology stand in the way of these priorities. Whatever works best for your company can be made to work best for your IT systems.

ABC Ltd has a heterogeneous collection of Windows / Linux servers located at a central data center, including a number of systems running VMWare, and some SQL Servers. The company needed to demonstrate to clients that they had a disaster recovery plan in place, and that all key data was backed up offsite.

Blueberry designed a backup plan based on three different data types used within the ABC network – conventional user files, SQL databases and large virtual machine images. A single new server was installed at a remote location, and configured with a Cisco firewall and a dedicated 24mbps DSL line. For the most important user files, a daily sync job was used to replicate the files securely over SSH. For the SQL databases, transaction log shipping was used in conjunction with Blueberry’s FTE system to replicate the databases to a parallel SQL server running on the backup system. For the large VM images, duplicity was configured to run on a slow incremental cycle, establishing backups of 200gb of VM images on a rotating monthly basis.