For business continuity, ACC’s approach is multifaceted. It is absolutely crucial to have a very good understanding of the type of data and applications to be protected before solutions are even discussed.
Double-Take Availability is a solution ACC has used for an extremely long time, and have significant expertise with this market leader. The entry level product Double-Take Move, has already achieved cult like status for its almost magical ability to migrate servers around from P2V, V2V, V2P – basically, anywhere, and with very little downtime. Move is a ‘one hit’ product, but Double-Take Availability is essentially an unlimited use license of Double-Take Move, with a number of extras thrown in.
The benefit of replicating at a byte level with DoubleTake is that you have granularity of control of what you want to replicate. A block level solution can’t offer you that. The other benefit of the byte level replication solution is that the target data is ‘readable’ whilst replication is in progress, meaning you can therefore see (and therefore monitor) the target end of the replication for your peace of mind that your DR solution is operating correctly.
ACC became involved in a quite complex DR solution for a customer a number of years ago that had been running byte level replication using Double-Take, however part of their DR requirement had clearly outgrown the solution that had initially been put in place many years before. Whilst Byte level replication is great for allowing you to pick and choose which files you protect, if you have a lot of files (in this case we are talking millions) then in order to check and verify files are copied over, scanning millions of files is going to take a huge amount of time. Shipping of SAN snapshots was an option explored, however this complicated the SAN solution, and required very careful orchestration of when snapshots took place.
SIOS SteelEye Protection Suite for Linux was a fantastic alternative to Double-Take, which replicated volumes containing huge numbers of small files to the DR site, in pretty much real time so no data loss in SAN snapshot windows. The SAN clusters were therefore free to focus on providing storage for production services and were not subject to getting their configurations tangled up with a DR solution. In addition to providing real time block copy replication to DR (DataKeeper), the LifeKeeper product enabled a simple SAMBA / CIFS network share to act as a clustered fileshare – clustering without the complexity.
DR solutions are generally not designed as backup solutions, as their prime function is to replicate. It’s important therefore to cover your backup & archiving requirements for your DR site. Our premiere backup solution vendor is Spectra Logic, a US firm with a rich history in backup and archiving invention.
A good archiving solution can help to dramatically reduce your production operating costs, as organisations have added Storage Area Networks (SAN) over the years, these are starting to fill up and are quite costly to expand and upgrade (not to mention simply keep running). By utilizing innovative archiving technology like Spectra Logic's Black Pearl and Arctic Blue solutions, these solutions enable you to offload huge amounts of ‘cold’ legacy data from your production / primary storage systems, but still make them available via the S3 interface if they are needed. So think of it as a kind of ‘live archiving’ solution.
With the amount of data you need to run in production significantly reduced, you might even save money on annual maintenance and support, and increase performance by buying in a smaller, faster replacement solution, as opposed to expanding the existing solution, and increasing the complexity and cost that goes with it.