Which are the Suitable Uses of Project Storage?
While central storage is extremly well suited for the storage of documents and the usage by teams, it is not suited for every range of use. This article describes the most important criteria.
Suitable Uses of Central Storage
Replacement of Local File Servers for Documents
Small teams (up to 100 members) often use their own file servers with up to 1 TB disc space. These servers can be easily migrated to project storage. Existing servers can then be decommissioned or used for other purposes.
Projects between Chairs, Faculties or Universities
In case that team members come from different part of TUM or from different universities, one of the cooperating organisations can allocate a part of its storage for the project an grant access to all team members.
Data Access from the Campus Net (MWN)
The LRZ makes sure that the local firewalls in the campus net (MWN) grant access to central storage. With local file servers this can hardly be done, since the port needed (445 for CIFS) is often blocked. Storage for CIP-Pools Central computing facilities for students can be configured to use the central storage. Thus users can access their Personal Storage easily.
Using the LRZ-VPN the central storage can be accessed from all over the world. Since central storage supports the SMB 2.0 protocol, the performance over WAN is quite good. Where VPN cannot be used, access to the files is possible via webdisk (https://webdisk.ads.mwn.de).
Uses with Restrictions
Local Servers and Central Storage
When your application runs locally and uses intensive I/O operations with single files located on Central Storage (eg. analysis of measured data, compilation of source code), you have to expect performance degradation. Make some experiments whether the performance is acceptable for you. As an alternative you should keep application and data either locally or to move to an centrally hosted environment at LRZ.
Disc Space for Large Media or Measurement Data
The Central Storage is less suited for large media or measurement data (more than 1 TB), since the capacity of central storage is currently not big enough. If you decide to keep your local file server or to buy a new one, we suggest to integrate the file server into the central Active Directory. Backup should be performed with help of services offered by LRZ.
We advise against image-based encryption on the central storage (eg. Truecrypt on folders). These encryption systems generate large files which the central storage can only handle as a whole. A restore of single files (also from snapshots) is then not possible. Neither it is possible to have concurrent access for different users.
In case you need encryption, we suggest the usage of file-based encryption methods (eg. PGP). As with any encryption you have to take care of the long term key management. In case that the key gets lost your data will be lost unrecoverably.
Simply Wrong Usage of Cental Storage
There are some use cases where we explictly advise against usage of Central Storage.
Database Servers on Central Storage
We advise against the operation of databases or simular applications (eg. MS Access) on Central Storage. Central Storage is optimised for normal file operations (activated oplocks). With databases this can lead to problems up to loss of data in case of loss of connectivity.
Central Storage shall not be used for backups. For backups exist specic service offerings from LRZ, which offer a longer storage of data and are optimised for this usage.
Home Directories for Linux/Unix
Native home directories for Linux/Unix are currently not available, since the offered CIFS protocol does not support some of the features needed by Unix (soft links). Nevertheless it is possible to mount central storage as a subfolder in the home directory. A joint usage of Project Storage is then possible without problems.