Disaster Recovery includes the process and procedures of restoring critical operations – in order to resume business as quickly as possible after a natural or human induced disaster strikes. This would include: regaining access to data, communications and all other critical processes necessary for normal business functioning.
A well-oiled plan requires the cooperation of an organized committee headed by an experienced pre-appointed chairperson. A comprehensive disaster recovery plan (DRP) must include plans for dealing with sudden loss of communications and the possibility of key personnel. Disaster recovery planning is part of a larger process known as business continuity planning (BCP).
Continuous data protection (CDP), also referred to as continuous backup, is a storage system in which all the data is backed up whenever any change is made. CDP generates an electronic journal of storage snapshots, one snapshot for every instant that data has been modified. It captures every version of the data that the user saves and allows the user/administrator to restore data to any point in time.
One of the major advantages of CDP is that it records every transaction that takes place in the enterprise. And, if the system becomes infected with a trojan or virus, or if a file becomes corrupted and the problem is not discovered until later, it’s still possible to recover the most recent clean copy of the affected file. Continuous data protection captures changes to data to a separate storage location.
Difference of CDP from Traditional Backup
The difference with CDP from traditional backup is that you’re not required to specify the point in time that you want to recover until you’re ready to perform a restore. With traditional backups, you can only restore data to the point the backup was taken – With CDP, there are no backup schedules. When data is written to disk, it’s simultaneously written to a second location, usually another computer over the network. This eliminates the necessity for daily scheduled backups.
Differences from RAID/Replication/Mirroring
The difference of CDP from RAID, mirroring or replication is that these only protect against a storage hardware failure by protecting the most recent copy of the data. If it’s a software problem that corrupts the data, these former technologies will simply protect the corrupt data. Continuous Data Protection will protect against some effects of data corruption by allowing an installation to restore a prior, uncorrupted version of the data. However, any transactions that happened between the time of corruption and the restoration will be lost and must be recovered through journaling or other means.
Backup Disk Size
For many enterprises, CDP requires less disk space than traditional backup. Most continuous data protection solutions save byte or block-level differences rather than file-level differences. How this translates is if you change one byte of a 100 GB file, only the changed byte or block is backed up. Traditional incremental and differential backups make copies of entire files.
Continuous data protection is becoming more widely used as businesses discover the advantages of maintaining a continuous journal of backups generated over time.
With the rise of information technology, where businesses rely on critical data information, the importance of protecting irreplaceable data has become a business priority in recent years. This is especially evident in information technology, where most companies are dependent on their computer systems as the critical infrastructure of their business.
Because of this, many businesses have become aware of the need to backup their data to limit data loss and to aid data recovery. Today, most larger companies are spending between 2% and 4% of their total IT budget on disaster recovery planning to avoid larger losses. Statistics reveal that businesses that had a major loss of computerized data, 43% never reopened -51% closed within two years – and only 6% survive long-term.
Disaster Recovery Strategies
Here is a list of common strategies for data protection.
- Backups made to disk on-site and automatically copied to off-site disk, or made directly to off-site disk
- Backups made to tape and sent off-site at regular intervals (preferably daily)
- Replication of data to an off-site location, which overcomes the need to restore the data (only the systems then need to be restored or synced).
- High availability systems which keep both the data and system replicated off-site, enabling continuous access to systems and data
In addition to preparing for the need to recover systems, organizations must also implement precautionary measures in order to prevent a disaster happening in the first place.
The following are ways to circumvent disaster and data loss:
- Local mirrors of systems and/or data and use of disk protection technology such as RAID
- Surge protectors — to minimize the effect of power surges on delicate electronic equipment
- Interruptible power supply (UPS) and/or backup generator to keep systems going in the event of a power failure
- Fire preventions — more alarms, accessible fire extinguishers
- Anti-virus software and other security measures
For a successful recovery of valuable data, an established and tested disaster recovery plan must be established before a disaster strikes!