Subsections
4.1 How to use interactive data analysis servers
Interactive data analysis servers are computers constructed for reducing and analyzing astronomy data interactively. Each server is accessible from user's PCs or the MDAS terminals in the open-use rooms with SSH connection. For non-interactive and resource-intensive calculation, the batch data analysis servers introduced in Section 4.2 should be used.
4.1.1 System configuration
Interactive data analysis servers consist of 32 servers (FUJITSU Server PRIMERGY RX2530 M2). These servers are classified into “kaim” servers and “kaih” servers from the difference of Random Access Memories(RAM) and Hard Disk Drives(HDD) they contain. A kaim server has 192GB RAM and 12TB HDD, and a kaih server has 256GB RAM and 51TB HDD. The Red Hat Enterprise Linux 7 is installed into both servers.
Table 4.1:
Specification of a kaim server
| Host name |
kaim[01-20].ana.nao.ac.jp |
| Machine |
FUJITSU Server PRIMERGY RX2530 M2 |
| Quantity |
20 |
| OS |
Red Hat Enterprise Linux 7 |
| CPU |
Intel Xeon E5 2667 V4 3.2 GHz 16 core |
| RAM |
DDR4 2400 RDIMM 192GB |
| HDD of the local disk region |
1.8 TB 2.5 inch SAS 10000 rpm |
| Size of the local disk region |
12.24 TB |
Table 4.2:
Specification of a kaih server
| Host name |
kaih[01-12].ana.nao.ac.jp |
| Machine |
FUJITSU Server PRIMERGY RX2530 M2 |
| Quantity |
12 |
| OS |
Red Hat Enterprise Linux 7 |
| CPU |
Intel Xeon E5 2667 V4 3.2 GHz 16 core |
| RAM |
DDR4 2400 RDIMM 256GB |
| HDD of the local disk region |
10 TB 3.5 inch NLSAS 7200 rpm |
| Size of the local disk region |
51 TB |
4.1.2 How to log-in
In order to log-in to an interactive data analysis server, the user's PC must be connected to the NAOJ network. To log-in to the server via the Internet, first establish a VPN connection from the user's PC to the NAOJ network using either the MDAS VPN service or NAOJ staff's VPN service.
The MDAS VPN service requires a VPN client software AnyConnect. Please download and install it according to the e-mail you received after completing the registration process of the VPN service.
In order to establish a VPN connection, launch the AnyConnect and connect to a VPN host server “kaimvpn.ana.nao.ac.jp” or “kaihvpn.ana.nao.ac.jp”. You should be required to input username and password, so please fill in your MDAS account and password.
Note that you can log-in to the kaim and kaih server from both the “kaimvpn.ana.nao.ac.jp” and “kaihvpn.ana.nao.ac.jp”.
Table 4.3:
MDAS VPN host server
| Host name |
|---|
| kaimvpn.ana.nao.ac.jp |
| kaihvpn.ana.nao.ac.jp |
Please refer to https://nethelp.mtk.nao.ac.jp/contents/en/node/4 for details.
An user log-in to an interactive data analysis server “kaim[01-20].ana.nao.ac.jp” or “kaih[01-12].ana.nao.ac.jp” with SSH connection4.1. Please launch a terminal emulator on your PC and input commands as follows.
$ ssh [-X] your_account@(kaim[01-20]|kaih[01-12]).ana.nao.ac.jp
4.1.3 Disk areas
The following disk areas are available from the interactive data analysis servers.
Table 4.4:
Disk areas available from the interactive data analysis servers
| Area |
Mount point |
Size per a mount point |
Soft/Hard limit |
Retention period |
| User home directory (NFS) |
/home[01-02] |
55TB |
140GB/150GB |
As long as your account in force |
| Large volume file system (NFS) |
/lfs[01-16] |
102TB |
30TB・32TB |
12 months |
| Local disk area of the middle-range servers |
/wkm[01-20] |
12TB |
NA/NA |
12 months |
| Local disk area of the high-end servers |
/wkh[01-12] |
51TB |
14TB/16TB |
12 months |
| NFS areas for data migration |
/ext_nfs[1-2] |
393TB |
9TB/10TB |
NA |
| NFS areas for data migration |
/ext_nfs3 |
306TB |
9TB/10TB |
NA |
- Before using the large volume file system or local disk area, please create a directory named your account under the disk areas.
- If your data volume reaches the soft/hard limit, application may not work normally.
- Files exceeding the retention period will be target of the periodic data deletion.
About NFS areas for data migration
- These areas, which became available on 17th October 2022, are for placing user data that you want to migrate to the next system. These areas will connect with the next system after the system replacement.
- Please refrain from analyzing data on these areas.
- These areas can be accessed from kaim and kaih servers.
- Periodic data deletion will not be carried out for the time being.
Periodic data deletion
Periodic data deletion will be carried out in the scheduled maintenance. The policy of this deletion is as follows:
- Target disk areas: the large volume file system and local disk areas exceeding utilization of 90%.
- Target files: files satisfying a condition that a difference between the date of the scheduled maintenance and timestamp(ctime) of a file exceeds the retention period.
- Date on which the target disk areas are determined: 2 weeks before the scheduled maintenance.
- Date on which data deletion is carried out: scheduled maintenance day.
In a disk area, if disk usage exceeds utilization of 90% as of 2 weeks before the scheduled maintenance, then the disk area will be a target of the periodic data deletion. If disk usage does not exceed utilization of 90%, then the disk area will not be a target. Files to be deleted are decided just before the scheduled maintenance.
Disk quotas
Disk quotas are set in MDAS to limit the amount of disk space used by each user. The amount of maximum available disk space (soft limit/hard limit) varies for each disk area.
- Soft limit: amount of maximum available disk space. An user can write data to the disk area even if the amount of data volume exceeds the soft limit. However, the user will become unavailable to write after seven days if the situation persists.
- Hard limit: amount of absolute maximum available disk space. An user cannot write data to the disk space if the amount of data volume exceeds the hard limit.
If your data volume reaches the soft/hard limit, application may not work normally, so you should copy or remove your data before reaching.
4.1.4 Network access control
Access (i.e. ssh, scp, or rsync) from the interactive data analysis servers to devices on the NAOJ network is not permitted for a security measure. In order to download data on an interactive data analysis server, please execute commands such as “scp” or “rsync” from user's PC to the interactive data analysis server.
$ scp your_account@(kaim[01-20]|kaih[01-12).ana.nao.ac.jp:<yourfile> ~/your/pc
ADC
2023-10-17
