Most companies have evolved comprehensive data backup and disaster recovery strategies for their central offices and data centres, but the same is rarely true of branch offices.
Attitudes to the importance of remotely stored information are changing, however, and new technologies that provide the means for reliable backups to be performed over low-bandwidth wide area network (Wan) links are giving IT chiefs food for thought.
‘It is a slow process, but organisations are being forced to look beyond the central office at the wider issue of disaster recovery. A lot of it is down to the need to consolidate information in a single data centre, which of course means that data has to be collected from the branch office to be protected,’ says Sue Clarke, senior research analyst at Butler Group.
‘Things have changed in the past year or so, to the point where more companies understand the importance of branch office data and realise that any irreparable loss would be serious – though just how serious varies from company to company,’ says Ovum principal analyst Graham Titterington.
One thing making many organisations sit up and take notice is the need to comply with industry legislation and corporate governance guidelines. Some companies have been slapped with fines because they have been unable to recover specific information from their data backups, and are understandably keen to avoid paying any more.
The Data Protection Act and Freedom of Information Act in the public sector demand that accurate records and file audit trails are retained, while the financial institutions are governed by Financial Services Authority and Basel II guidelines. Certain sectors, such as the pharmaceutical industry, have always been regulated tightly when it comes to data retention and retrieval.
‘Most firms are up against the general obligations of company directives, and sometimes either code of conduct or terminal reports if they are listed on the stock exchange,’ says Ovum’s Titterington. ‘But all of these rules are vague and do not include anything specific telling the IT department that it has to back up data at branch offices.’
Deciding whether or not to protect information stored at branch offices may be easier than choosing which technology to do the job, however. The range of solutions to the problem is as broad as the ranks of vendors offering them.
The latest innovations include continuous data protection, which replicates small changes to critical data at regular intervals or every time a new version of a file is saved, and data de-duplication, which strips out repeated content from multiple sites to store a single copy at a central location, accessible by everybody.
Both are disk-based technologies that work to reduce the amount of data actually being backed up, but they are equally reliant on robust network connectivity to be able to replicate that information to a central site.
The common hurdle here is that most branch offices use low-bandwidth Wan links, often based on 2Mbit/s DSL connections or leased lines that struggle to handle the traffic load without affecting other mission-critical applications sharing the capacity.
Two technologies designed to make it quicker to transfer and access large amounts of data over these connections are Wan optimisation and wide area file services (Wafs). Some vendors have recently merged both into single solutions aimed squarely at solving the problem of disaster recovery for companies with multiple, widely distributed offices.
Wafs are concerned with making it quicker and easier to access files over the Wan, and optimisation concentrates on speeding up Wan traffic and making the most of the bandwidth available. Both seek to allow remote sites to access shared, centrally stored resources at local area network-like response times, eliminating latency, jitter and retransmission delays over low-bandwidth Wan links that could force users to wait minutes to open, back up or restore large files.
Wan optimisation is not specifically a disaster recovery technology but it can help during backup and restore, while the real benefit of using Wafs is that they can span multiple operating systems across a large number of sites, so that storage and replication entities appear as a single file system. Such technology use makes systems much easier to implement and manage, says Claus Egge, programme director for European storage systems research at IDC.
‘Wafs come into play when an enterprise is effectively spanning multiple sites and data needs to be transferred between them, not just for backup and recovery but as a straightforward requirement for daily business operations,’ he says.
‘An operating system (OS) thinks it owns everything you can see, but most businesses run more than one OS, or at least different flavours of the same OS. It is interesting to have a single view of things going on across different file systems.’
But combined Wan/Wafs solutions are still in their relative infancy, and demand a high level of in-house network storage expertise to keep them operational and effective. Some companies prefer to use hosted online backup services that collect and store the data for them, installing software on client PCs that periodically backs up files to a secure data centre over the internet.
Ovum’s Titterington believes that online backup is growing in popularity, but is unsuitable for large companies with higher volumes of data. Companies using Wafs also need to be careful that any natural disaster that befalls their offices does not affect the disaster recovery site as well.
‘It is an increasing trend, not an epidemic,’ he says. ‘People are more aware of the benefits of having online backup storage available, but there is a lot of beefing about how far away from the primary site you have to be to properly protect against disaster, and a continuing debate about whether the backup is synchronous or asynchronous.’
Most companies, if they are backing up branch office data at all, are still using a tried-and-trusted method to do it; information is copied to tape, and the tape is trucked off to be safely stored at either another site or at a central repository.
Inergy Automotive Systems, an international developer and manufacturer of plastic fuel systems with 25 offices in 18 different countries, uses Wan optimisation to make the most of the bandwidth that each site has available, but it does not replicate information from those offices to a central disaster recovery facility. Instead, IT manager Arun DeSouza uses localised tape backups ‘to break up the risk and spread it around’.
‘It is normal policy for us to offset backups straight to tape, in most cases using HP Ultrium drives, and using a standard rotation of tapes at every site. The monthly backup tapes go off-site, but the dailies stay on-site, while some of our larger offices send off tapes bi-weekly,’ he says.
‘There is still a huge amount of data backed up to tape, and not just in branch offices. Information lifecycle management and tiered storage approaches are nothing new, because we had hierarchical storage management in the past.
‘Certainly, organisations are putting more data on disk in the short term to make it more quickly accessible, but they are still archiving it onto tape.’
What the experts say
Backing up branch offices does not necessarily have to be too much of a problem.
They are all generally connected to either a private wide area network (Wan)
connection or to the internet, and there are usually backup tools stored at the
data centre that can do the job anyway.
Graham Titterington, principal analyst, Ovum
Wan optimisation is not really part of the disaster recovery side, more of a
proactive downtime minimisation strategy. It is disaster prevention rather than
recovery.
Arun Desouza, IT manager, Inergy Automotive Systems
It helps me sleep at night knowing that we have more copies of critical data on tape, a medium that is universally accepted and understood. But in some satellite offices, the amount of data they work with on a day-to-day basis makes the justification for employing tape-to-tape backup in small offices questionable.
Jason Hamlett, IT manager, Fulcrum Pharma
Until network accelerators came on the scene, we had no option but to deploy
servers at every site and back up every device locally, because the speed of the
Wan was not appropriate for anything else.
Ian Wood, head of IT, Wildfowl and Wetlands Trust
For any IT manager looking at a set of sites where there are long-distance
implications, it is an obvious thing to bring in wide area file services (Wafs)
and Wan optimisation companies and to listen to what they have to say. The tapes
on trucks argument is not a winner when companies can do things electronically;
firms are setting up connections to do things remotely because they want the
resilience of -fast duplication.
Claus Egge, programme director for European storage systems research, IDC
Products such as Remote Office Backup by Symantec make replicating data at
smaller sites simpler, and there is a big push on applications such as
enterprise content management, which provides centralised repositories for the
storage of all the unstructured information in the organisation, on workers’
laptops and local hard drives.
Sue Clarke, senior research analyst, Butler Group
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