Thecus Technology i Series User Manual

 

When rebuilding, the status of PD/VG/UDV is “R”; and “R%” in UDV will display the ratio in 
percentage. After complete rebuilding, “R” and “DG” will disappear. VG will become 
complete one. 

 

  

 

 

 

The list box doesn’t exist if there is no VG or only VG of RAID 
0, JBOD.  Because user cannot set dedicated spare disk for 
these RAID levels. 

 
Sometimes, rebuild is called recover; these two have the same meaning. The 
following table is the relationship between RAID levels and rebuild. 
 

Disk striping. No protection of data. VG fails if any hard drive 
fails or unplugs. 

 

Disk mirroring over 2 disks. RAID 1 allows one hard drive fails 
or unplugging. Need one new hard drive to insert to the 
system and rebuild to be completed.  

Extension to RAID 1 level. It has N copies of the disk. N-way 
mirror allows N-1 hard drives fails or unplugging. 

Striping with parity on the dedicated disk. RAID 3 allows one 
hard drive fail or unplugging. 

Striping with interspersed parity over the member disks. RAID 
5 allows one hard drive fail or unplugging. 

2-dimensional parity protection over the member disks. RAID 
6 allows two hard drives fails or unplugging. If it needs to 
rebuild two hard drives at the same time, it will rebuild the first 
one, then the other by sequence. 

Mirroring of the member RAID 0 volumes. RAID 0+1 allows 
two hard drives fails or unplugging, but at the same array. 

Striping over the member RAID 1 volumes. RAID 10 allows 
two hard drives fails or unplugging, but at different arrays. 

The abbreviation of “Just a Bunch Of Disks”. No protection of 
data. VG fails if any hard drive fails or unplugs. 

 

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