How does it work?
Windows Agent
The windows agents pick up a schedule from the BDR Server. This schedule includes the following information:
Days to run: Mon x Tue x Wed x Thu x Fri x Sat x Sun
Start time: 5.00
End Time: 22.00
Frequency: 0.15
The example above will run Monday - Saturday, starting at 5.00am and ending at 10.00pm with a frequency of 15 minutes.
This would create multiple 15 minute snapshots that can either be mounted to recover files, folders and email or turned into a virtual machine.
Each server can have a separate schedule and it is possible to configure the Windows Agent to throttle it's CPU and network bandwidth usage.
Backup Process.
The first backup taken will be a complete block level image of the disk volumes selected, this image is compressed generally at a ratio 2.5 : 1, the backup data is stored on the storage server and encrypted with 256 bit encryption.
After the first backup image is complete, subsequent backups or snapshots are taken of the data blocks that have changed. This ensures that subsequent snapshots execute quickly and use the minimal amount of disk space on the storage server.
The storage server in turn will collapse the 15 minutes snapshots into a daily snapshot, daily snapshots are collapsed into weekly, and weekly snapshots into monthly.
Monthly snapshots are retained indefinitely unless cleared down.
Synchronization & offsite storage
There are three methods that can be used to maintain a copy of data off site, all of which are automatic and monitored.
- Daily Synchronization to USB drive or NAS
- BDR to BDR replication (over internet or WAN)
- Secure upload of snapshots to data centre (currently US based)
USB / NAS
USB synchronization is by far the simplest method and suitable for data sizes up to 2.5TB.
Existing 2.5" host powered USB drives currently store 1TB of data.
3.5" adapter powered USB drives can store 2.5TB (storage sizes as of Jan 2010)
BDR to BDR
BDR to BDR replication is designed to provide a downstream copy of your live servers at a disaster recovery site. This can be over a WAN, VPN or standard internet connection, adequate bandwidth between the local and remote BDR is required in order to ensure the remote server is kept up to date. The data stream between the two BDR server is compressed and encrypted and can be throttled during business hours if required.
The down stream BDR is capable of virtualizing any of the live servers being backed up by the local BDR, although IP address changes may be required depending on your network topology.
Upload to Data Centre
It is possible to purchase data centre storage and have the BDR automatically upload it's snapshot data to the data centre.
The first full backup of each server is synchronized to removable media which is shipped to the data centre and copied to storage.
Once this copy has taken place incremental data is upload automatically via secure FTP, this process is monitored by the monitoring software.
In the event of a disaster effecting the site, the servers are virtualized onto a new BDR at the data centre which is in turn shipped to site.
Currently data centre storage is located in the US which may not be suitable for UK sites as BDR shipment from the US can take 1 - 3 days.
Virtualization
A failed server can be virtualized on the BDR appliance in less than 1 hour, this process can be as quick as 20 minutes depending on the type of server being virtualized and the model of BDR.
The virtualization process is controlled via a wizard from the management console and can be accessed remotely over the internet via a secure portal.
This is ideal for branch offices as it is possible to recover a full server or server(s) without the need to travel to site, thus maintaining a high level of server and application availability.
File recovery
Any of the backup snapshots can be mounted on the BDR as an additional drive, this drive or its sub folders can then either be shared on the network allowing end users to recover their own files, or used by an administrator to drag and drop data, back to live storage.