RAID Capabilities

As mentioned earlier, the StorCenter has RAID support on the internal drives. Figure 8 shows the disk-format screen where the RAID level can be specified.

Figure 8: RAID Setup

In spanning mode, the two internal drives are treated as one big drive. In striping mode, access to the drives is split, giving increased performance but no fault tolerance. In Mirroring mode, each drive is a copy of the other, giving increased security in case of disk failure and increased read performance, with the downside being your total storage space is halved.

To test the capability to recover from a disk failure, I shut the system down, opened up the case, unplugged the SATA cable from one drive, and powered it back up.

When the system powered back up, the documentation indicated that I should see alternating red and blue LEDs on the front panel to indicate a disk failure, but instead there was no indication that anything was wrong. I could still access my shares and use them normally. The capacity of the drive was as before.

Only when I dug a bit deeper and displayed the "Disk Management" display did I notice an inconspicuous status showing that now the unit was in "Spanning" mode instead of "Mirroring" mode. This was the only indication that one of the drives was missing (Figure 9).

Figure 9: Disk Management

If you weren't specifically looking for an issue, you'd never know that a drive had died. This is where a good logging and alerting subsystem would be beneficial, but unfortunately the StorCenter has neither logs or alerts.

To check out the recovery capability of the drive, I shut it back down, reconnected the second drive, and powered back up. As before, there was no obvious indication that anything had changed. The "Disk Management" screen looked the same as before, except now the status read "offline" (Figure 10).

Figure 10: RAID Offline

I thought there would be a "repair" option, but the only option available was a destructive "format." So I guess if you need to recover, it will be up to you to back up your data before reconstructing the RAID mirror.

When I selected the format option, I was warned that it was a destructive operation, but I went ahead. While the format was occurring, a red LED blinked on the front of the StorCenter, and the Disk Management screen showed a percentage complete message. The whole operation took around two-and-a-half hours, which made me think that maybe it really was re-mirroring my data; however, when it completed, everything I had stored was deleted. In addition, all my user accounts, groups, and shares were gone.

As far as other options available under the "Disk Management" menu (Figure 10), you can see the ability to set a spin-down time for drives, which is nice for people like me who have systems that are idle most of the time. Unfortunately, as mentioned earlier, this mode either doesn't work or doesn't save much power.

You can also see an option that allows USB drives to be mounted automatically when plugged in. Iomega advertises support for drives formatted in FAT, FAT32, and NTFS in a read-only mode.

Network Setup

Under network setup there are the various options you'd expect, such as DHCP vs. manual setup, workgroup name or domain name, etc. And since this is a gigabit- capable unit, you can also turn on jumbo-frame support (Figure 11).

Note that only a 9K jumbo frame size is available, instead of the selectable sizes available in other products.

Figure 11: LAN setup

Tags: Iomega, NAS, RAID,

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