Snapshots

2010-08-18T20:39:09Z

Rayhan: /* CIFS */

Snapshots are a implementation of copy on write that allows for a file system to quickly take a point in time copy of the file system and provide access to the data through a .snapshot directory.

We provide [[Snapshots]] on our [[ONStor]] filers to certain file systems.

==Snapshot Policy==

Our core file systems in the department are on a 4 hour snapshot cycle. Snapshots are taken at,

{| style="color:green; background-color:#ffffcc;" cellpadding="5" cellspacing="0"
| 12am
| 4am
| 8am
| 12pm
| 4pm
| 8pm
|}

We retain up to 8 hourly snapshots, 2 daily snapshots and 1 weekly snapshot.

These are available on the following [[OpenLAB]] file systems,

===[[NFS]]===
* /nfshomes
* /fs/www
* /fs/www-users
* /fs/ftp

===[[CIFS]]===
* \\umiacsfs02.umiacs.umd.edu\nfshomes
* \\umiacs-webftp.umiacs.umd.edu\www-umiacs
* \\umiacs-webftp.umiacs.umd.edu\www-users
* \\umiacs-webftp.umiacs.umd.edu\ftp-umiacs

Please see [[SnapshotFileSystems]] for a list of our file systems that have snapshots in the department.

==Snapshot Restoring==

If you find that you have mistakenly deleted a file and it was created/written to before the last snapshot[1]. You can restore the file by going to the directory where the file was and changing into the .snapshot directory and then using a normal copy operation to copy it back to the directory where you would like it. Please note that the .snapshot directory is hidden and may not appear when you do a directory listing.

''[1] - If a file was created or modified after the last snapshot then you can potentially lose up to 4 hours of work in a worse case scenerio. Please make sure you save your work throughout the day.''

Example:

Changing to my quotes directory.
<pre>
[derek@novelty quotes]$ pwd
/nfshomes/derek/work/quotes
</pre>
I see that i have a quote called '''redhat_sole_source_2007.doc'''.
<pre>
[derek@novelty quotes]$ ls
dlt_pdf_quote2007.pdf Quote_300086759.html redhat_solesource.pdf
dlt_pdf_quote.pdf Quote_353511914.html soleSource2007.pdf
dlt_quote.pdf Quote_367512608.html soleSource.pdf
dy1014.xls Quote_367884529.html UMD_008.xls
Quote_250530976.html redhat_sole_source_2007.doc
</pre>
<pre>
[derek@novelty quotes]$ ls -la redhat_sole_source_2007.doc
-rw-r--r-- 1 derek derek 39936 Jan 23 2007 redhat_sole_source_2007.doc
</pre>
I will remove it from the current file system.
<pre>
[derek@novelty quotes]$ rm redhat_sole_source_2007.doc
</pre>
As you can see it no longer is there.
<pre>
[derek@novelty quotes]$ ls
dlt_pdf_quote2007.pdf Quote_250530976.html Quote_367884529.html UMD_008.xls
dlt_pdf_quote.pdf Quote_300086759.html redhat_solesource.pdf
dlt_quote.pdf Quote_353511914.html soleSource2007.pdf
dy1014.xls Quote_367512608.html soleSource.pdf
</pre>
I am going to go into the last hourly snapshot '''hourly.0'''
<pre>
[derek@novelty quotes]$ cd .snapshot/hourly.0
</pre>
As you can see the quote is still here.
<pre>
[derek@novelty hourly.0]$ ls
dlt_pdf_quote2007.pdf Quote_300086759.html redhat_solesource.pdf
dlt_pdf_quote.pdf Quote_353511914.html soleSource2007.pdf
dlt_quote.pdf Quote_367512608.html soleSource.pdf
dy1014.xls Quote_367884529.html UMD_008.xls
Quote_250530976.html redhat_sole_source_2007.doc
</pre>
I copy it back to the original directory.
<pre>
[derek@novelty hourly.0]$ cp redhat_sole_source_2007.doc /nfshomes/derek/work/quotes/
</pre>
Change back to the original directory.
<pre>
[derek@novelty hourly.0]$ cd /nfshomes/derek/work/quotes/
</pre>
And it is back.
<pre>
[derek@novelty quotes]$ ls
dlt_pdf_quote2007.pdf Quote_300086759.html redhat_solesource.pdf
dlt_pdf_quote.pdf Quote_353511914.html soleSource2007.pdf
dlt_quote.pdf Quote_367512608.html soleSource.pdf
dy1014.xls Quote_367884529.html UMD_008.xls
Quote_250530976.html redhat_sole_source_2007.doc
</pre>

__NOTOC__

NASUsers

2010-08-18T20:38:40Z

Rayhan: /* Web Pages */

===Web Pages===

Your UMIACS web page is online at

http://www.umiacs.umd.edu/~username.

You can edit it as

/fs/www-umiacs/users/username

on any supported UNIX system and you can mount it via [[CIFS]] with as

\\umiacs-webftp.umiacs.umd.edu\www-users

This file system has regular backups with our [[TSM]] service and has [[Snapshots]] for easy user restores.

===Personal FTP Sites for Distributing Data===

Your ftp site is online at

ftp://ftp.umiacs.umd.edu/pub/username

On any supported UNIX workstation, you can access your ftp site as

/fs/ftp-umiacs/pub/username

Windows users can map it as a network drive from

\\umiacs-webftp.umiacs.umd.edu\ftp-umiacs\pub

You can also upload files using [[FTP]], [[SFTP]], and [[SCP]] through openlab.umiacs.umd.edu.

Please note that anyone with an internet connection can log in and download these files so please to do not use your ftp site to store confidential data.

This file system has regular backups with our [[TSM]] service and has [[Snapshots]] for easy user restores.

===Personal FTP Sites for Accepting Uploads===

You can also accept uploads through ftp at

ftp://ftp.umiacs.umd.edu/incoming/username.

To access the uploads on any supported UNIX workstation go to

/fs/ftp-umiacs/incoming/username

Please copy and then delete the uploaded files. Windows users can map the directory as

\\umiacs-webftp.umiacs.umd.edu\ftp-umiacs\incoming.

Please note that your peers will not be able to list or read the files that they upload, since this would allow unrelated third parties to upload and distribute files through our ftp service.

This file system has regular backups with our [[TSM]] service and has [[Snapshots]] for easy user restores.

===Conduit - DEPRECATED===

Other NFS based file systems are available via [[CIFS]]

\\conduit.umiacs.umd.edu

===Usage Guidelines===

Personal NAS is configured to be highly available and modest in both size and usage. Please store large or heavily accessed data sets in a dedicated project storage directory that is tuned for your application.

Please avoid storing shared project data in personal storage allocations. Separating project data from personal data will simplify administration and data management for both researchers and staff.

UMIACS - User contributions [en]

Snapshots

NASUsers