7.2 External storage devices

Operation of the external storage devices were terminated at the end of February 2023.

Terminal workstations in the MDAS provide external storage devices for input/output and bringing/take out of large observation data. We describe the devices name and the usage of the devices connected to the terminal workstations.

7.2.1 Available external storage devices

A part of the terminal workstations has an external LTO tape drive and Blu-ray disk (BD) drive. Additionally, each terminal workstation have an internal BD drive.

Table 7.3: A list of the external storage devices

Type	Model	Place	Host	Device
External LTO tape drive	LT70 USB	Open-use room of the Subaru building	sbt13	/dev/st0
External BD drive	UBD-4070HQ	Open-use room of the Subaru building	sbt13	/dev/st1
Internal BD drive	BU40N	Open-use room of the Subaru building, Room 101 of the ALMA building	sbt[01-13], alt[01-09]	/dev/sr0

Each drive supports the following medias.

Table 7.4: A list of the supported medias

Type	Media
External LTO tape drive	Ultrium5 (Read Only), Ultrium6, Ultrium7
External BD drive	BD-R, BD-R DL, BD-R XL, BD-RE, BD-RE DL, BD-RE XL, DVD-ROM, DVD-R, DVD-R DL, DCD-RW, CD-ROM, CD-R, CD-RW
Internal BD drive	BD-ROM, BD-R, BD-R DL, BD-R XL, BD-RE, BD-RE DL, BD-RE XL, DVD-ROM, DVD+/-RW, DVD+/-R DL, DVD+/-R, CD-ROM, CD-R

• BD drives support to write to writable medias.
• BD drives may not be able to read and write a DVD-RAM media.
• BD drives have needed time to write to a DVD+R media in our writing test (more than 4 times the DVD-R media, more than 8 times the BD-R media).
• External BD drives have been able to write to BD-R XL and BD-RE XL medias in our writing test without a manufacturer's guarantee.
• Internal BD drives can write to BD medias, but we do not recommend it. If you write your data into BD medias, please use the external BD drive connected to the “sbt13”.

7.2.2 How to use external storage devices

1. How to write to CD/DVD/BD medias using the GUI software

The internal BD drive built in the terminal workstations can write to CD/DVD medias and the external BD drive connected to the “sbt13” can write to BD medias by using the GUI software. Please refer to the following PDF files for details.

• CD/DVD：https://www.adc.nao.ac.jp/MDAS/ug/image/DVD-GUI-E.pdf
• BD：https://www.adc.nao.ac.jp/MDAS/ug/image/BD-GUI-E.pdf

2. How to write to BD medias using the CUI commands

The external BD drive connected to the “sbt13” can write to BD-R and BD-RE medias by also using the CUI commands. You have to carry out the following steps on the “sbt13”.

BD-R media (write-once media)

After moving to the “/work” region which is a local disk region of the terminal workstations, please make an image file and write the image file into the BD-R using the “drmake” and “drtran” commands.

$ cd /work/your_account
$ drmake -i ./data -F [udf150 or udf250] | drtran -t /dev/sr1

• The external BD drive is not able to add data into a recorded BD-R if it has free space.
• We recommend that you carry out these operation under the “/work” region which is a local disk region of the terminal workstations because we have found that the image file is not made on the “/lfs[01-16]” and these operation require enough partition volume and quota.
• The UDF 1.50 is a popular file system available on a lot of OSs, but the maximum data size of the UDF 1.50 is 8.5 GB. If you need to write data more than 8.5 GB, you have to choice the UDF 2.50 of which the maximum data size is 100 GB. However, your OS may not supports the UDF 2.50 because the UDF 2.50 is a new file system.
• It takes about 5 minutes to write about 5 GB data into a BD-R (1-6x).

Please refer to the following commands if you only make a image file or only write a image file.

[Make a image file]
$ drmake -i ./data -o data.iso -F [udf150 or udf250]
[Write a image file]
$ drtran -t /dev/sr1 -s ./data.iso

BD-RE media (re-writable media)

In order to write to the BD-RE media, you have to use the “olx*” commands. We recommend that you use a new BD-RE media because it is necessary to format the BD-RE media in the following steps.

a.

Execute the “drtran” command in order to erase data with high-speed. This operation is not necessary if the media is formatted. After formatting, the media will be rejected.

$ drtran -t /dev/sr1 -x1 -l
device name = [/dev/sr1]
Media Load
Get Media Information
MediaType(BD-RE BLANK)
Start High Speed Erase
Media Unload
Normal End

b.

Execute the “olx_format” command in order to format the media.

$ olx_format -f /dev/sr1

c.

Execute the “olx_mount” command in order to mount the media.

$ olx_mount /dev/sr1 /mnt

d.

Copy your data to the media. We recommend that you copy data after moving to “/mnt”.

$ cd /mnt
$ cp -r /work/your_account/data .

e.

Execute the “olx_umount” command after writing.

$ olx_umount /mnt

f.

Eject the media after unmounting.

$ olx_umount -e /dev/sr1

• It is necessary to format (olx_format) a media first time only. If you have a formatted media, you can start from “olx_mount” (step [c]).
• After executing the “olx_mount” command (step [c]), you can use Unix commands such as “cp” and “rm”. However, we do not recommend to use the “mv” command because warnings may be displayed.
• If you cannot copy your directory to the media (step [d]), make a image file of the directory using the “drmake” command and copy the image file to the media.
• It takes about 50 minutes to write about 5 GB data into a BD-RE (1-2x).

3. How to use tape device

How to input/output data

You can input/output data to/from tape devices by using the “tar” or “dd” command. We show how to dump and restore data with the “tar” command here.

Dump

Dump all files under /lfs[01-16]/your_account/test1 to a tape using the “tar” command.

$ cd /lfs[01-16]/your_account/test1
$ tar cvf /dev/st0 .

Restore

Restore tar formatted data from the tape to under /lfs[01-16]/your_account/test2.

$ cd /lfs[01-16]/your_account/test2
$ tar xvf /dev/st0 .

It takes about 3 minutes for dumping/restoring 5 GB data.

How to use body of the tape device

Eject button:

You push this button when you eject a tape cartridge from the drive.

Power button:

This button turns on/off the power of the device.

The meaning of the body lamp

operating state

• Green lamp Light: The power is ON and you can normally use this.
• Green lamp Blinking: The device inns reading/writing a tape cartridge.

Encryption

• Green lamp Light + White lamp Light: An encrypted tape cartridge is loaded.
• Green lamp Blinking + White lamp Blinking: Encrypted data is in reading/writing.

Error

• Orange lamp Light + Error code: A hardware error of the drive is occurring. If the device is not recovered by turning off/on the power, please contact the operator.
• Orange lamp Blinking + Error code: A hardware error of the drive is occurring. When the drive needs cleaning, then error code “C” is displayed. Please contact the operator.