One of the best reasons to use a multi-disk array (like RAID 5) is that it automatically rebuilds as soon as you replace the defective drive. The only thing the user will need to do is identify and replace the malfunctioning drive. This is easily done by referring to the drive-bay LEDs on the corresponding front-panel.
If you need to double-check* a faulty drive, simply remove it from the case and connect it directly to the motherboard of a desktop computer. Again, you will use your Disk Management Utility to identify any file-system errors. If the drive fails to register within your disk management utility at all, then you can be sure it is time to replace it. Luckily many modern Tera-Bytes sized drives come with a 2 or 3 year warranty from their respective manufacturers. This should be a primary concern when selecting what HDDs you want to use with your CADA-U3E4. *Refer to our Tech Guides online for information about how to error-check a drive: http://www. cavalrystorage.com/manuals.aspx
After you replace a drive, you will want to check the progress of the rebuild. Even though your drive may be available for usage immediately, the rebuild may run silently in the background for hours or even days in the case of very large arrays. This is normal and shouldn’t affect drive performance. But, you will still want to track the progress. For this, you will need to locate the ‘Event Log’. This is a standard list of all recent activities and is included with most modern applications. Click the ‘Basic Mode’ tab on the left and then click ‘Event Log Viewer’ (second icon from the top). This will show you if a member disk fails or if the array is currently rebuilding. Likewise, sudden power-outages and drive failures will also be listed here. The Event Log Viewer is an invaluable
tool!
PRECAUTIONARY MEASURES
In order to maintain a continuously-healthy array without ever loosing data, you must monitor your drives regularly and replace any defective drives ASAP. In 4-disk arrays (RAID 3, 5, and 10) it only takes two defective drives to wipe your data clean!
Monitoring your drives is as easy as glancing up at the LEDs on the front panel of your CADA-U3E4. CADA-NAS owners can utilize the automatic email-function to alert them whenever a drive fails. You’ll need to check with your email-client or system-administrator for the specific port and protocol settings necessary to configure the automatic emails. But for CADA-NAS owners, this is a VITAL function.
ADDITIONAL FEATURES
Your CADA-U3E4 also features firmware updating capabilities as well as a spin-down timer. Rebuild Priority is also configurable in the ‘Advanced Mode>RAID Settings’ tab. We recommend setting it to 10. But power-users may choose to default to a specific value.
The spin-down timer can be used to slow the rpm of your drives while not in use. But, be careful with this setting. In busy workgroups, spin-down timers can cause abnormally long access cues to form. In these instances, it is best to leave this setting at zero.
AFTER THE STORM: REBUILDING A DAMAGED ARRAY