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--- computing:department:unix:file_storage [2015/02/20 19:21] – [Project Data storage] allan
+++ computing:department:unix:file_storage [2016/02/02 13:52] (current) – [sshfs] allan
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-<box 20% right right-clear red|More Information>
-{{indexmenu>:computing:department:unix}}
-</box>
 ====== Data storage on Unix ======
-===== Home directory storage and backups =====
+===== Home directories =====
 Your home directory on the Unix cluster has a usage quota, to avoid too much space being taken by individual users. The standard quota is normally somewhere around 10GB. You can see your current usage and quota by visiting [[https://www.physics.umn.edu/resources/myphys/|MyPhys]].
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 If you run into your quota, and after reviewing your file usage find that you still need more space, you can reply to the warning email to request a change from us. Please understand, however, that the amount of space available is limited. Your home directory is not intended for large research data sets, for which separate project-specific storage should be used.
-<note>Please make sure you don't send intensive writes to your home directory, as this causes slowdowns for all other users on our system. We may be forced to kill any processes which are causing such problems</note>
+**Home directories should not be used for data-intensive computations, such as input or output for condor batch jobs.**
 The home directories are backed up nightly, and in addition filesystem "snapshots" are created every few hours (currently at 09:00, 12:00, 15:00, 18:00).
-===== Project areas =====
+===== Shared project areas =====
-If you need a shared area for your project where multiple people can develop or store code, we can create such an area and back it up for you. This is intended for small-scale usage; if you need to store large data sets then read under "Project data storage" below.
+If you need a shared area for a group or project where multiple people can develop or store code, we can create such an area and back it up for you. These are made available under the ''/local'' hierarchy. These are intended for relatively small-scale usage, such as shared program areas - large data sets should be stored in the research data areas.
-===== Project Data storage =====
+===== Research data storage =====
-Other file systems are provided for research or project-specific data, under the **/data** hierarchy. This storage space is **purchased by the research group**. It can take the form of simple single drives in linux workstations, part of the shared research RAID pool, or dedicated RAID systems for large-scale storage needs.
+Other file systems are provided for research or project-specific data, under the **/data** hierarchy. This storage space is **purchased by the research group**. It can take the form of simple single drives in linux workstations (though this is discouraged), part of a shared research storage pool, or dedicated systems for large-scale storage needs.
-These file systems are usually named either after the research group group (for a server-based RAID volume), or with the name of the workstation which hosts it (for a simple data drive), and contain further directories organized by user or by project. These areas should be used for large data sets and storage for local processes. Note that these areas are provided by the //automounter// - they are not activated until they are first accessed, so they won't necessarily appear in the output of commands like ''df''.
+These file systems are usually named either after the research group group (for a fileserver volume), or with the name of the workstation which hosts it, and contain further directories organized by user or by project. These areas should be used for large data sets and storage for local processes. Note that these areas are provided by the //automounter// - they are not activated until they are first accessed, so they won't necessarily appear in the output of commands like ''df''.
-**Warning** these areas are generally **not backed up** by default. If you have a large amount of data which requires backup, you should talk to us about the available options.
+===== Backups =====
+<note warning>
+  * Unix **home directories** are backed up daily.
+    * Older files may need to be recovered from snapshots or from tape. Complete tape backups are currently made monthly and retained for 6 months.
+  * **Research data areas are not backed up**
+    * Data areas on our ZFS storage have nightly //snapshots// which are kept for 2 days - these can help you recover from accidentally deleted files.
+    * Linux RAID storage does not have snapshots.
+    * If you have critical research data which requires backup, this can be arranged for moderate data sizes (eg < 10TB). Please talk to us about the options.
+    * Local data drives in workstations are **never** backed up.
+</note>
 ===== Local "scratch" storage =====
@@ Line 40: / Line 49: @@
-===== Remote access to file systems using sshfs =====
+===== Remote access to data =====
+The security model of Unix NFS is too weak to permit exporting it to any systems which are not part of the Physics cluster. Some alternative methods of transferring data include...
+==== globus ====
+Please see [[:computing:department:data:moving:globus]]
+==== sshfs ====
-You can use //fuse// (the userspace filesystem driver) to mount any remote filesystem which you have ssh access to. You can use this to access files from other systems outside of Tate Lab. For example:
+You can use //fuse// (the userspace filesystem driver) to mount any remote filesystem which you have ssh access to. Although this is not a high-performance solution, you can use this to access files from non-Physics linux systems. For example:
   mkdir ~/mnt  #create a place to put it, can be called anything you want.

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