Difference between revisions of "File servers"

Revision as of 11:52, 3 July 2013

DTU Compute IT Support provides a number of filsystems. Some of the more "important" ones are mentioned below.

List of file systems:

/home/<username> \\nas1\<username>:
Description: Standard UNIX homedirectory. Mountet as x:\ on Windows PC. Every user has exactly one folder on nas1.
Backup frequency: Daily
Live data: yes
Snapshots: yes

\\nas1\winhome\<username>:
Description: A CIFS-only share mountet as h:\ on Windows PC.Every user has exactly one folder
Backup frequency: Daily
Live data: yes
Snapshots: yes

/project/<projectname> \\san1\project\<projectname>:
Description: Areas with greater capacity than HOME but lower backup frequency. Ask DTU Compute ITSupport for a folder.
Backup frequency: Weekly
Live data: yes
Snapshots: no

/nobackup/<projectname> \\imm-nas2\<projectname>:
Description: Larger disk areas mainly for performing calculation on the linuxgrid. Ask DTU Compute ITSupport for a folder.
Backup frequency: None
Live data: yes
Snapshots: yes

/nobackup/<projectname> \\san1\nobackup\<projectname>:
Description: Larger disk areas mainly for performing calculation on the linuxgrid. Ask DTU Compute ITSupport for a folder.
Backup frequency: None
Live data: yes
Snapshots: no

/groups (UNIX servers) \\nas1\groups:
Description: Files for group based projects
Backup frequency: Daily
Live data: yes
Snapshots: yes

/www/docs (UNIX servers) \\www2\docs:
Description: Web pages for courses projects etc.
Backup frequency: Daily
Live data: yes
Snapshots: no

/www/home/<username> (UNIX servers) \\www2\<username>:
Description: Personal www pages. Every user has exactly one folder.
Backup frequency: Daily
Live data: yes
Snapshots: no

\\nas1\backups\<username>::
Description: A CIFS share for making backup of Windows PC using immbackup.
Backup frequency: Daily
Live data: no (should always be a copy of data found on a local hard drive)
Snapshots: yes

/backup/<username> on userbackup1.imm.dtu.dk:
Description: A share for making backup from linux/Mac PC's using rzyncbackup.
Backup frequency: Daily
Live data: no ( should always be a copy of data found on a local hard drive)
Snapshots: yes

\\nas1\software::
Description: Software for Windows. Mountet as s:\ drive on Windows PC connected to the DTU Compute Windows domain.
Backup frequency: Daily
Live data: yes
Snapshots: yes

\\nas1\software_mac::
Description: Software for Mac OS
Backup frequency: Daily
Live data: yes
Snapshots: yes

Snap shots and how to use them

On all the filesystems hosted on nas1 snapshots are made: A snapshot is a read-only copy of a filesystem at specific time. Snapshots does not use ones quota.

Frequency

Snapshots are taken

Hourly: 10:00, 12:00, 14:00 16:00
Nightly: 24:00 (i.e. midnight)

The latest 4 hourly are kept and the last 5 nightly are kept.

How to access them

From a UNIX client:
In the directory where the old file was, change to the folder .snapshot. In this directory there is 9 directories:

drwxr-xr-x 205 hc sys 65536 Oct 19 20:47 hourly.0
drwxr-xr-x 205 hc sys 65536 Oct 19 20:47 hourly.1
drwxr-xr-x 205 hc sys 65536 Oct 19 20:47 hourly.2
drwxr-xr-x 205 hc sys 65536 Oct 19 20:47 hourly.3
drwxr-xr-x 205 hc sys 65536 Oct 20 20:50 nightly.0
drwxr-xr-x 205 hc sys 65536 Oct 19 20:47 nightly.1
drwxr-xr-x 205 hc sys 65536 Oct 18 22:53 nightly.2
drwxr-xr-x 204 hc sys 65536 Oct 17 21:22 nightly.3
drwxr-xr-x 204 hc sys 65536 Oct 16 07:32 nightly.4

The latest hourly snapshot is named hourly.0, 2nd latest hourly.1, etc.
Note the folder .snapshot is not visible, i.e. it will not show in a "ls -la" listning.
If the folder .snapshot does not exist it is because the parent folder was created after the latest snapshot was taken. Also, if only some of the "hourly" and "daily" folders exist it is because the parent folder was not created at the time of the missing snapshot.

Hint: the command find will pr. default search the .snapshot directory the command find . -name some-name is issued. Use the command find * -name some-name instead. This can speed up the process with a factor 10 or better.

From Windows client:
Either like UNIX, i.e. change to a hidden folder ~snapshot and browse to file of interest. Or find the file/folder of interest, take properties of it and look at Previous Versions tab.