Solaris and external USB disks

Short tutorial on how to connect, format, mount, detach and reconnect external USB disks.

The used disk is WD20EARS connected to a USB port via Sharkoon Quickport Pro cradle.

Basically, you need only two commands:

  • rmformat – to determine the device name/path
  • zpool – to do the rest (create ZFS, mount, attach and detach)

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QNAP NAS, eSATA , Solaris and backing up

Given:

  • QNAP TS-439 Pro NAS with 4 x WD20EADS in RAID-5
  • eSATA/USB Sharkoon QuickPort Pro SATA cradle
  • WD20EARS
  • 1.7TB data on RAID-5

Guess, how long will it take to back up 1.7TB of mostly big files to a directly connected eSATA disk using standard GUI commands?
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Hard drives: Enterprise vs. Desktop

What to choose for a home server? The most important difference is not the accelerometers or MTBF but whether the disks will be used in RAID’s.

An excerpt from Western-Digital FAQ:

When an error is found on a desktop edition hard drive, the drive will enter into a deep recovery cycle to attempt to repair the error, recover the data from the problematic area, and then reallocate a dedicated area to replace the problematic area. This process can take up to 2 minutes depending on the severity of the issue. Most RAID controllers allow a very short amount of time for a hard drive to recover from an error. If a hard drive takes too long to complete this process, the drive will be dropped from the RAID array. Most RAID controllers allow from 7 to 15 seconds for error recovery before dropping a hard drive from an array. Western Digital does not recommend installing desktop edition hard drives in an enterprise environment (on a RAID controller).

Western Digital RAID edition hard drives have a feature called TLER (Time Limited Error Recovery) which stops the hard drive from entering into a deep recovery cycle. The hard drive will only spend 7 seconds to attempt to recover. This means that the hard drive will not be dropped from a RAID array.

If you install a RAID edition hard drive in a desktop computer, the computer system may report more errors than a normal desktop hard drive (due to the TLER feature). Western Digital does not recommend installing RAID edition hard drives into a desktop computer environment.

Source: What is the difference between Desktop edition and RAID (Enterprise) edition hard drives?