• Home
• Articles Archive
• Features List

• Media Pack
• Contact Us
• Subscribe

FalconStor Software CDP

From STORAGE Magazine Vol 7, Issue 7 - October 2007

The uptake of virtual machine technology is growing massively across a wide range of market sectors as more and more businesses see the benefits it can offer. The latest release of VMware's ESX Server will undoubtedly accelerate this growth even further and FalconStor aims to get the best from this with its new CDP (continuous data protection) virtual appliance solution. Based around its highly successful IPStor iSCSI software, CDP is designed to run specifically in ESX Server v3 environments where it provides a range of data protection facilities.

CDP uses a Linux kernel which runs on a virtual machine and provides iSCSI virtual disks to client systems. It can protect both virtual and physical servers and offers a range of key features including replication, snapshots and fast data and system recovery.

Installation is nicely automated as you simply load the CDP disc in the ESX Server system, mount it and run the install routine which creates the virtual appliance. CDP can use virtual drives or an RDM (raw data mapping) which allows it to use any external storage device that ESX Server supports. At the client system you install the Microsoft iSCSI initiator and FalconStor's DiskSafe utility which automates iSCSI target logon and provides the replication, or mirroring, services. For snapshots, you load the relevant agent on each system and FalconStor provides options for a wide range of applications.

The DiskSafe management console is used to declare a virtual appliance to the client and to create protection polices. You can opt to protect a disk or partition and choose continuous or periodic protection. In continuous mode, DiskSafe replicates changes to the primary data as they are written whilst periodic mode sends the changes, or deltas, at selected intervals. DiskSafe can change modes dynamically depending on criteria such as the I/O load on the application server or latency and available bandwidth for WAN links.

The snapshot feature works at the block level and uses journals to record all changes between each snapshot right down to each millisecond. This comes into its own for data recovery as you can pick any point in the journal such as a quiet period where the recovery is likely to be most successful. It's also useful in instances where a user created and then deleted a file in between snapshots. The agents communicate at the API level and prior to taking a snapshot the Exchange agent, for example, will put the application into a hot backup mode where it flushes its write buffers to ensure the data is in a consistent transactional state.

CDP offers an excellent range of swift disaster recovery possibilities. If a physical server fails it can be converted to a virtual server literally in minutes as you declare a CDP mirror or snapshot directly to the ESX Server system, create a new virtual machine and assign the disk to it. The VMware converter installs the appropriate drivers on the virtual boot disk and the machine is switched on to replace the failed system. You can also use the bootable recovery CD created by DiskSafe to bring up hot-standby system at remote locations. This allows the server to contact the CDP appliance over iSCSI where it loads the same OS and applications as run on the primary server but accesses the data remotely on the CDP appliance. Next, you simply create new local drives and use DiskSafe to recover the data.

Virtual machines are proving to be a sweet-spot for iSCSI and FalconStor's latest CDP takes full advantage of this. It's very simple to deploy, delivers sophisticated replication tools and facilitates swift data and system recovery. ST

Product: Continuous Data Protection
Supplier: FalconStor Software
Tel: 0208 757 5690
Web site: www.falconstor.com
Price: £3,995 exc VAT ($7995) - supports 16 hosts, 64 snapshots per LUN and includes 5 DiskSafe licences