System Backup & Disaster Recovery
The main purpose backup is to make a copy or multiple copies of data, and save them onto separate media. When the data on the main system is crashed or lost, the copied version can be retrieved onto the main system. Benefits of backup include:
- Reduction of the risk of critical data lost
- Capability to retrieve the previous versions of data, in case that the current data is damaged from virus or malware
- In case of crisis or disaster, in which the main system cannot be accessed, the backup data that is kept in a separate location can be used instead to ensure business continuity
There are many methods for data backup:
- Use system restore, which is a normal tool for data backup and recovery
- Backup data onto external devices such as external hard-drive
- Use commercial backup software such as ArcServe, Symantec, etc.
There are also many types of storage, normally used for data backup, including CD/DVD, external hard-drive, DAS, NAS, SAN, tape cartridge, etc.
Disaster Recovery (DR)
DR is the process of retrieving data from a backup media, which might be located at the same site or at a separate site, onto the main system, so that the corresponding application can continue running. For those companies in which their businesses depend on the continuity of mission-critical applications, data backup to a separate DR site is highly recommended.
DR site can be classified as follow:
- Cold DR Site This type of DR site prepares a basic IT infrastructure waiting for a system to be installed; when a crisis or a disaster occurs and the primary system cannot be accessed, an identical system – including OS, application and its data – will be installed at DR site. End-users will then access this secondary system at DR site, until the primary system is recovered from failure. It normally takes up to few days to make the secondary system at a cold DR site ready for the end-users.
- Warm DR Site At a warm DR site, a secondary system is completely installed and put into “standby” stage; when a crisis or a disaster occurs and the primary system cannot be accessed, the secondary system will be turned on. Normally, the data at the secondary system is not always identical to that of the primary system, so the latest data must be updated into the secondary system before serving to end-users. So, it may take several hours to be able to use the secondary system at a warm DR site.
- Hot DR Site Sometimes called mirror site, the secondary system at DR site is always ON, and continuously gets replicated data from the primary system. When the primary system fails, the secondary system can take over the workload to serve end-users with very minimal downtime.
How to choose Backup & DR solutions?
Apart from the basic factors such as data size, data growth rate, and allocated budget, another important factor for the consideration is the service level agreement (SLA) of the mission-critical applications, in which the organization is targeting at. And SLA can be typically defined by RTO and RPO.
- Recovery Time Objective (RTO) is the maximum period of time used to recover a failure system back to the normal condition, ready to serve end-users.
- Recovery Point Objective (RPO) is the maximum period prior to the system failure time, in which data can be lost.
Based on the business size, the recommended backup solutions can be summarized as follow:
|
Small
|
Medium
|
Large
|
Enterprise
|
|
| Data Amount |
1 – 3 TB
|
3 – 7 TB
|
7 – 15 TB
|
> 15 TB
|
| Qty of Servers |
3 – 5 units
|
6 – 10 units
|
11 – 20 units
|
> 20 units
|
| Target Backup Media |
Disk and/or |
Disk and/or |
Disk and/or |
Disk and/or |
| Type of Storage |
Local Disk of
Backup Server |
NAS
|
SAN
|
SAN
|
| Type of Tape Drive |
LTO6 |
LTO6 |
LTO6 |
Virtual Tape
Library |
| RPO |
1 day
|
1 day
|
12 hours
|
6 hours
|
| RTO |
1 day
|
1 day
|
12 hours
|
6 hours
|
We have a technical team who specialize in backup & DR solutions, based on multi-vendors environment, we can design and implement an appropriate solution to exactly fit your requirements.
Besides RTO and RPO, network bandwidth must also be taken into consideration in order to select an appropriate DR solution, especially for DR sites that are connected to the primary site via WAN connections.
We have a technical team who specialize in backup & DR solutions, based on the targeted SLA, the locations of DR sites and multi-vendors environment, we can design and implement an appropriate solution to exactly fit your requirements.
No data
No data