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we were never able to see the drives so we are restoring from backup.
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we were never able to see the drives so we are restoring from backup.

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We have a server that has a Raid 10 with four 250GB WD drives. &nbsp;After installing some updates, the server was restarted; however, it did not come back up. &nbsp;It indicates &quot;no OS&quot;. &nbsp;When we go into the raid manager, it indicates three drives as &quot;offline&quot; and one as &quot;unavailable&quot;. &nbsp;When we try to create a new raid, it indicates there is not enough HD space. What should we do to get the OS back online?
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We have a server that has a Raid 10 with four 250GB WD drives.  After installing some updates, the server was restarted; however, it did not come back up.  It indicates "no OS".  When we go into the raid manager, it indicates three drives as "offline" and one as "unavailable".  When we try to create a new raid, it indicates there is not enough HD space. What should we do to get the OS back online?

Raid 10 failure

Servers are computing devices that are similar to desktop computers in that they have the same basic components, but are significantly different in size, configuration and purpose. Servers are usually accessed over a network, and many run unattended, without a computer monitor, input device, audio hardware or USB interfaces. Many servers do not have a graphical user interface (GUI), and are configured and managed remotely. Servers typically include hardware redundancy such as dual power supplies, RAID disk systems, and ECC memory, along with extensive pre-boot memory testing and verification. Critical components might be hot swappable, and to guard against overheating, servers might have more powerful fans or use water cooling.

Server Hardware

RAID stands for Redundant Array of Independent Disks.

RAID is data storage technology that allows multiple drives to be used together as a single virtual drive for reasons such as fault tolerance, reliability and performance. 

There are several different levels of RAID that determine how the data is stored and the level of redundancy achieved across the drives.