Disk array

Employees and collaborators of IBOT can take advantage of the data storage capacity that amounts to a total of 180 TB, for running analyses on the Průhonice cluster and for long term storage. The basic disk usage allowed for members of the ibot group is 2 TB (7 GB for the others). Shared folder with restricted access to specific users can be also implemented. The storage is backed up in the CESNET infrastructure. For disk quota increase or for the creation of shared folders please contact the administrators.

How to access the disk array

Access to the disk array is possible from any node in the MetaCentrum, where it can be found at /storage/pruhonice1-ibot/ with the home directories located in /storage/pruhonice1-ibot/home/.

One can access the storage through a direct connection (using any client application such as FileZilla) by SFTP, SCP or SSHFS at tilia-nfs.ibot.cas.cz (alias storage-pruhonice1-ibot.metacentrum.cz).

Graphical clients

Use FileZilla, WinSCP, etc. and enter:

Host (target server): storage-pruhonice1-ibot.metacentrum.cz or tilia-nfs.ibot.cas.cz

Port: 22

Protocol: SFTP, SCP, SSH2

Credentials for MetaCentrum.

FileZilla usage

Access via command line

# Copy files to and from the storage... scp -r local/files USER@tilia-nfs.ibot.cas.cz:~/server/folder/ scp -r USER@tilia-nfs.ibot.cas.cz:~/server/files notebook/folder/

Shared folders

Shared folders are located on the storage in folder /storage/pruhonice1-ibot/shared/GROUP_FOLDER/ accessible from all MetaCentrum frontends and computing nodes. There is UNIX group available for every shared folder, administered in Perun. Any user can be group administrator. Login uses MetaCentrum credentials, group admin can than click to „Group Manager“, „Select Group“, „Select VO: MetaCentrum“ and select group whose members should be administered.

All files, regardless if they are located in shared folders, or in users' home directories, are counted into personal file quota of particular user (shared folders do not have separate quota). If needed, user can request increase of the quota.

Files newly created in directory /storage/pruhonice1-ibot/shared/GROUP_FOLDER/ have automatically set group owner GROUP. If it would not happen, user must change group owner. It is then necessary to alter the permissions so that data are accessible exclusively for members of the group using commands like:

# Change group owner chgrp -R GROUP /storage/pruhonice1-ibot/shared/GROUP_FOLDER # Change folder permissions find /storage/pruhonice1-ibot/shared/GROUP_FOLDER/ -type d -exec chmod 770 '{}' \; # Change file permissions find /storage/pruhonice1-ibot/shared/GROUP_FOLDER/ -type f -exec chmod 660 '{}' \;

Because of security of files and necessity of their share, user must be well aware of UNIX permissions! Wrong settings of the permissions might result in data loss (e.g. as by wrongly working script of another user). Alongside it is necessary to set up permissions that another members of the group have full access to them. These tasks can be done in graphical SFTP clients (e.g. FileZilla, WinSCP), however usage of command line is faster and simpler. In case of issues contact maintainers.