Nearline Disks
This page provides information on the nearline disks that can be used in all courses, with the exemption of the free-of-charge courses for academic organizations and trial courses for civilian agencies. Shirokane2 are available for use.
What are Nearline Disks?
Summary
Nearline disks are a form of low-cost, high volume disk storage. HGC provides 2 types of nearline disks:
Type |
Summary |
Premium Nearline Disks |
Although access is slow from a lustre domain, they are faster than new nearline disks. In more concrete terms, you can access the disks from Shirokane2 at 40Gbps. Premium nearline disks also include the backup of the ~/backup directory. For more details on backups of ~/backup directories please see here |
New Nearline Disks |
Although access is slower than premium nearline disks, these disks can be used for 1/3 of the price. These nearline disks are closer in price to generic stand-alone HDDs, so they provide an amazingly economical option. New nearline disks offer access of 1Gbps. |
Method of Use
Hosts with Access
Unlike lustre domains that provide a home directory, there is a restriction on the number of hosts that can access the disks. This is because accessing nearline disks from multiple hosts simultaneously can cause deterioration in performance. The disks can be used from Shirokane2 using the following methods:
Shirokane2 |
ngw |
Run "% ssh ngw" and login using SSH |
intr.q |
After logging into ngw, run "% qlogin" and login to intr.q |
cp.q |
Submit a job to do a copy using "% qsub -l cp " |
Nearline disks cannot be accessed from queues other than intr.q and cp.q (sjobs.q, mjobs.q, ljobs.q, lljobs.q, exclusive queues, etc.). Please note that submitting jobs that access nearline disks will result in an error.
Nearline Disk Path
The nearline disk paths are below:
System | Type | Path |
Shirokane2 | Premium Nearline Disks | /near/data/groupname/ |
New Nearline Disks | /nnear/qdata/groupname/ |
If you want to check the name of the group you belong to, please run the command below.
$ groups
groupname hgcXXXX
Verifying Used and Available Space
Please see
Find out how much space has been used, and how much space is available on the nearline disks.
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