Rebuilding a NAS appliance RAID array

Disks fail, and RAID arrays need rebuilding. Be prepared for the worst – and keep your clients’ data safe.

Hard disks don’t last forever. The bathtub curve gets you every time, with old drives wearing out and losing data. That’s why RAID systems are a good idea, with RAID 1 mirroring information between two disks and RAID 5 using an array of three or more disks to create a recoverable disk array that can rebuild after any one disk in the array fails.

Business-grade Network Attached Storage (NAS) appliances form the backbones of many small office networks, providing a central file and print service where there’s no need to invest in a full-scale server. They also provide additional storage capacity which can reduce the load on an SBS server. Many of these appliances are embedded Linux systems using consumer disks and running them with a workload very different from their original design specifications. Disks will fail, and you will have to rebuild the array.

Use the Web interface on a NAS appliance to manage RAID arrays.
Use the Web interface on a NAS appliance to manage RAID arrays.
Rebuilding a NAS array is a relatively simple (if time-consuming) task. You’ll need to have a disk of the same size as the failed disk. Some NAS arrays support using larger disks as a path to increasing the available storage, so it’s worth checking the documentation. If possible, you should have appropriate disks in stock to reduce client downtime – if you don’t know what’s in the NAS use the hardware diagnostics and think about buying spares when you populate a bare NAS carcass. Once the disk has been replaced, use the NAS appliance’s user interface to rebuild the array. The process is relatively simple, and most systems will prepare the drive and copy data automatically. There can be an issue with early versions of the Buffalo TeraStation Pro firmware. The system flash memory on these devices only contains a boot loader – most of the OS is held as a partition on the RAID array. In early OS releases a disk failure prevented the OS from booting and a disk replacement meant either purchasing a preformatted disk from Buffalo or installing new firmware. To avoid similar problems, make sure that all your clients’ arrays are running the latest software releases.

A 500GB rebuild can take more than eight hours – so be prepared for a late night with plenty of coffee while you watch the progress bars and refresh your browser, or make sure the customer knows the drive won’t be available until you’ve tested it the next morning. 



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Posted: Jun, 11 2009

LG Launch their new NAS including Blu ray drive

LG have a new NAS product launching shortly, rumour has it that the pricing will be approx £650. For this price you will have 4 x 1TB Hard drives and a blu ray writer included. Nothing on the market can compare to this as it boast all the features of its competitors and more!!!



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If you're supporting en users who need to transfer files by FTP occasionally, explaining how to use FTP every time can get frustrating. Map an FTP site as a custom network location and they can do it through the familiar Explorer window. If you only have a couple of machines you can choose Tools >Map Network Drive… in Explorer and click the link 'Connect to a Web site that you can use to store your documents and pictures' to open a wizard that creates a network location. Select 'Choose a custom network location', type in the FTP address and fill in the user name and password. You can also create mapped drives and network places on the Environment tab of the user's Active Directory object - but if you have a lot of users to set up, put it in the logon script for the user profile under Active Directory Users and Computers.
If you're running into problems with Group Policy Objects, check this handy summary of the rules at read more


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