5.3 – Drive & RAID Issues Flashcards
Drive & RAID Issues
- Should have a back-up
- Never keep all data on ONE drive
- HD dies = dead [not much you can do]
LED = Light emitting diode status indicators
o Used to help you diagnose issues
o Tell if drives are functioning
o Most RAID systems = lights should be blinking green
—Amber = may be a dead drive – pull drive out / put new one in
Synology box
-
RAID array external box
—NAS with giant RAID inside
Grinding Noises & Clicking Sounds
o Drive is dead / dying
o BACKUP right away if the drive can still be used
o Clicking = maybe can read information
o Replace if hear either noise
Bootable Device is NOT Found
o System could be set to boot to the wrong drive in the BIOS
—Change boot order from HD to USB, looking for OS
o Drive is dead
o OS could be corrupt
Data Loss / Corruption
o Restore from backup if data is lost / corrupt
o Data corrupted reasons = HD problems, drive failing, memory failing, viruses, application crashes
—Reinstall app, OS, new memory, new HD
RAID failure
o Depending on the RAID you may need to
—Replace a failed drive & let the RAID REBUILD
—[RAID 1, 5, 10] have redundancy
—Replace the failed drive & RESTORE all data from backup [RAID 0]
special software = tells you which RAID failed
—Pop in new drive & rebuild RAID = only if have redundancy = 1 drive dies, machine OK
—Click option to rebuild & it rebuilds itself
S.M.A.R.T = Self-Monitoring, Analysis, & Reporting, Technology failure
o Monitoring system included in computer hard disk [HDD] & SSD
o Function is to detect & report various indicators of drive reliability with intent of anticipating imminent hardware failures
o Software that could tell you of imminent drive failure
Extended read / write times &
input / output op per sec [IOPS]
o Looks at how fast drivers are working
o Can describe
o Old drives = IOPS very slow / very small
o SSD = IOPS High [100,000]
o IOPS Read much faster than write cycle
—Sometimes read from drive & NOT write
o SSD = much more read cycles than write cycles
—Some limited = 10,000 write cycles: hundreds of years
Missing Drives in OS
o BIOS not set to correct drive
o Drive is dead
o OS is corrupt
o Before replace drive = unplug drive & plug in
