Data safety for CIS can be managed with servers with redundant components and RAID arrays or replicated servers that provide very high availability for CIS.

Single Server
The single Server can be configured with redundant a power supply to power the components if the main power supply should fail. It also has a disk array with 4 hard drives and an additional hot swap drive as a spare. A disk array provides built in RAID 5 striping and parity over the 4 drives and provides the capability to continue working without any interruption should one of the disks fail. Should a drive fail, the hot-spare will immediately, without user intervention, be added to the RAID array and brought online to replace the failed drive and restore redundancy. The 4 drive array still provides full redundancy it just does not have an available hot swap drive until the failed drive is replaced. This scenario permits the repair and/or replacement of the defective parts without shutting down the server thus the clinic will continue operations without the users being aware that there has been a component failure.

Although the single Server scenario provides a very reliable high availability server, this scenario does not address the failure of the server’s other electronic components. If one of those should fail then the clinic would be down until that is repaired. P & P supplies hardware which includes 3 years of on-site support with a 24/7 - 4 hour response time for servers supplied directly from the hardware manufacturer.

Server Replication
To ensure that there is no significant down time, ever; P & P can also supply Replication technology to provide a cost effective solution to clients that want a high availability system where down time is minimal if the main server fails and the replication software activates the backup server. P & P can optionally supply a fault tolerant version of CIS that will automatically redirect all users to the failover server and there will be no need for users to log in again.

Replication is achieved by having 2 identically configured servers with special replication software running on each. P & P uses Double-Take which copies data changes at the byte (character) level to the second server each time there is a change on the master server. This is a software based replication where the servers are loosely coupled and don’t have to be at the same physical location. With this technology one can achieve high availability and protect data against potentially disastrous events such as a fire by locating the second server at a different location connected via the Internet.

An additional advantage of this scenario is that backups can be performed on the replicated server which means that backups can be run at any time while the system is live. The replication data is stored on the primary server until the backup is completed and then is applied to bring the two servers back into synch.

Data Backup
Backups can be performed using tape drives, large capacity external disk drives, or an online service provided by Critizal. Aside from performing data backups regularly it is also very important that the backup media be moved off site to enable data recovery in case of a major disaster such as a fire or flood at the clinic site.

In the case of a single server solution the backups must be scheduled and performed off-line. This is usually accomplished by scheduling backups after hours.

In the case of the Server Replication solution the backups can be performed live at any time since the operation can be performed on the replicated server. Data is held on the main server until the backup is completed and then the two servers are brought back into synch.