Seven levels of disaster backup and recovery
SHARE 78 international standards to define the disaster recovery system as seven levels, which correspond to different disaster recovery schemes in terms of functions, application scope, etc. So the user should be divided into different levels.
The real disaster recovery must meet three factors: first, the system components, data are redundant, that is, one system fails, the other system can keep the smooth data transmission; Secondly, it has the property of long-distance. Because disasters always occur within a certain range, sufficient long distance can ensure that the data will not be destroyed by a disaster. Third, disaster recovery systems should pursue all-dimensional data Replication, also known as the "3R" (Redundance, Remote, Replication) of disaster recovery.
And SHARE 78 international standard for the definition of the disaster recovery system has seven levels: from the simplest, only locally tape backup, to the backup tapes are stored in the different ground, and then to establish real-time switch long-distance backup system, application system recovery time can also be from a few days to grade class hours to minutes and seconds or zero data loss, etc. At present, there are corresponding disaster recovery schemes for these seven levels. Therefore, when selecting disaster recovery schemes, users should focus on distinguishing their respective characteristics and application scope, and judge which level of schemes to choose according to their own requirements for the disaster recovery system.
Level 0: Backup without exception
The level-0 disaster recovery plan data is only backed up locally, no data is backed up in other places, and no disaster recovery plan is made. This approach is the cheapest disaster recovery solution but has no real disaster recovery capability.
In this disaster recovery scheme, the most commonly used is backup management software with a tape drive, which can be manual or automatic loading tape drive. It is the foundation of all disaster recovery solutions, which have been widely adopted from individual users to enterprise users. Its characteristic is the user investment is less, the technical realization is simple. The disadvantage is that in the event of a local catastrophic disaster, all local backup data will be lost and the business cannot recover. But Vinchin can do remote backups, Onsite/Offsite Backup Copy。Vinchin Backup & Recovery allows users to copy VM backups to offsite storage, restore backup copies from offsite to the local site, restore backup copies at offsite production environment in case any disaster occurs.
Level 1: Remote backup is implemented
The level-1 disaster recovery plan is to back up the critical data to the local magnetic tape and then send it to the remote place for storage. However, there is no available for backup center, backup data processing system, and backup network communication system in the remote place, and there is no disaster recovery plan. After a disaster, the data is restored using a new host and a remote data backup medium (magnetic tape).
This is a low-cost solution, using local backup management software, in the local disaster, can restore the backup data shipped from other places to the local, business recovery. But it is difficult to manage, meaning it is difficult to know what data is where, and the recovery time depends on when the hardware platform is available and ready. In the past, it has been widely used as a means of disaster recovery in different places by many large enterprises engaged in critical business production. At present, this level of programs in many small and medium-sized websites and enterprise users are more used. For users who require rapid business recovery and massive data recovery, this scheme is not acceptable.
Level 2: Hot backup site backup
The level-2 disaster recovery plan is to backup key data and put them in different places. Disaster recovery plans are made for sites with hot backup capacity. In the event of a disaster, the hot backup host system will be used to restore the data. The difference between it and the level-1 disaster recovery plan is that there is a hot backup site in another place, which has a host system. Usually, the backup management software in another place will be used to back up the data delivered to the data backup medium (magnetic tape) in another place to the host system. When a disaster occurs, you can quickly take over the application and resume production.
As a result of the hot standby center, the user investment will increase, the corresponding management personnel to increase. Technology implementation is simple, the use of a remote hot backup system can be in the local catastrophic disaster, rapid business recovery. However, in this disaster recovery plan, the backup medium is sent to another place by means of transportation, and the data stored in the heat backup center in another place is the data of the last backup, so the data may be lost for several days or even weeks. This is intolerable for critical data resilience.
Level 3: Online data recovery
The level-3 disaster recovery plan is to backup and stores the critical data in different places through the network, formulate the corresponding disaster recovery plan, have a backup center, and equip with part of the data processing system and network communication system. The class program features electronic data transmission instead of transportation to transmit backup data, thus increasing the speed of disaster recovery. The use of remote backup management software will be transferred through the network to the remote data backup to the host system. In the event of a disaster, critical data needed can be quickly recovered over the network, and the recovery time for critical applications can be reduced to a day or an hour by switching over the network. The cost of this tier is increased by the high network requirements required to keep the backup site running continuously.
Level 4: Scheduled data backup
The level-4 disaster recovery plan is based on the level-3 disaster recovery plan. The backup management software is used to automatically backup some critical data to other places at regular intervals through the communication network, and the corresponding disaster recovery plan is formulated. In the event of a disaster, restore the operation of the critical business system by using the backup center's existing resources and remote backup data. The function of Smart Backup Strategy by vinchin，flexible & smart backup Strategies helps to do backup & restore jobs as scheduled according to your actual demands in different scenarios.
This level scheme is characterized by the use of automatic backup management software backup data to the remote, remote hot backup center stored data is the timing of backup data, according to the backup strategy, the loss of data, and recovery time to reach the level of days or hours. Input costs also increase due to higher requirements for backup management software equipment and network equipment. However, due to the characteristics of this level of backup, the business recovery time and the amount of data loss can not meet the requirements of critical data disaster recovery in key industries.
Level 5: Real-time data backup
The level 5 disaster recovery plan USES hardware mirroring technology and software data replication technology on the basis of the previous several levels, that is, the data in the application site and the backup site can be updated. The data is mirrored between the two sites and synchronized by remote asynchronous submissions, and because critical applications use dual online storage, only a small fraction of the data is lost in the event of a disaster and recovery time is reduced to minutes or seconds. The higher requirements for storage systems and data replication software increase the cost significantly.
The scheme of this level is the most widely used one because it can not only ensure the current transaction is not affected, but also replicate the data generated by the transaction to other places in real-time. For this reason, many manufacturers have disaster recovery solutions based on their own products. For example, remote copy of data based on intelligent storage server launched by storage manufacturer EMC; Remote copying of data based on system software provided by VERITAS, etc.; Database replication solutions provided by database vendors Oracle and Sybase. One drawback of these solutions, however, is that off-site backup data is in Standby rather than available in real-time, so it takes some time for business recovery after a disaster. Ideally, the backup site should not only be a separate backup system but also be active and provide production application services, thus providing rapid business takeover, while backup data can be transmitted in both ways, with loss and recovery time of minutes or even seconds. Currently, Goldengate's global replication software can provide this function. With Vinchin Backup & Recovery instant VM Recovery helps to recover TB sized VMs in 15 secs, all business recovery in 1 min, minimized the break-off time of critical businesses. And, Quick-verify Recovery Availability, recovering the VM backups to Data Verification Area ( which is isolated with Production Area) by Instant VM Recovery, helps to quick-verify the availability of backed up data.
Level 6: Zero data loss
Level 6 disaster recovery is the most expensive and fastest way of disaster recovery. It is the highest level of disaster recovery and USES a dedicated storage network to synchronously mirror critical data to the backup center, where data is not only confirmed locally but also in other places (backup). Because the data is written to two sites in a mirror image, the remote disaster recovery system retains all the data when the disaster occurs, realizing zero data loss.
This scheme utilizes dual online storage and complete network switching capability when all data is updated locally and remotely, which not only ensures complete consistency of data but also provides automatic switching capability in storage and network environment. In the event of a disaster, not only does the backup site have all the data, but the application can take over automatically to achieve zero data loss. Redundant channels are usually provided in the connection of optical fiber equipment in both systems in case the working channel fails. Of course, due to the high requirements for the storage system and storage system private network, the user's investment is huge. The users who adopt this disaster recovery mode are mainly large enterprises with relatively strong financial strength and telecommunication level enterprises. However, in the practical application, the fully synchronous mode has a great impact on the operation efficiency of the production system, so it is suitable for the critical data system with few production transactions or non-real-time transactions. At present, few users adopt the disaster recovery scheme of this level.
Interested Blogs More
3 ways to realize Virtual-to-Virtual(V2V) migration
Save data before fire, why DR solution a must-have for your business?
Classification of information systems
Notes after your data loss！
Introduction to VMware virtualization storage principle and data recovery method