backup:snapshot
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backup:snapshot [2007/06/05 18:17] – damir | backup:snapshot [2007/09/20 15:49] – cangiani | ||
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A **snapshot** in our case is the same thing, but related to file and directories. If we take a **snapshot** of a particular directory or file, we can always access this file **as it was**, no matter how much we changed the file or if the file was completely deleted. We can access this type of information at least until we delete the **snapshot** we took. | A **snapshot** in our case is the same thing, but related to file and directories. If we take a **snapshot** of a particular directory or file, we can always access this file **as it was**, no matter how much we changed the file or if the file was completely deleted. We can access this type of information at least until we delete the **snapshot** we took. | ||
+ | |||
+ | |||
+ | ===== For NetApp Filer Users (IPG users) ===== | ||
+ | |||
+ | ==== How it works ==== | ||
The filer that serve the IPG user create these **snapshots** automatically and in a trasparent fashion, the user's don't have to manage any configuration to activate this feature. | The filer that serve the IPG user create these **snapshots** automatically and in a trasparent fashion, the user's don't have to manage any configuration to activate this feature. | ||
The system generate a **snapshot** of the user's directory every hour and save it in a separate space (not really, but just to maintain the things simple). The users can access these data just browsing the homedir. No need to use some strange and unfriendly software. | The system generate a **snapshot** of the user's directory every hour and save it in a separate space (not really, but just to maintain the things simple). The users can access these data just browsing the homedir. No need to use some strange and unfriendly software. | ||
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- | ====== User point of view ====== | + | |
+ | |||
+ | ==== User point of view ==== | ||
Every user of the LTHC, LTHI and LCM labs can find inside his/hers homedir on the central filer an hidden directory named **.snapshot**. Inside this directory exists others directories: | Every user of the LTHC, LTHI and LCM labs can find inside his/hers homedir on the central filer an hidden directory named **.snapshot**. Inside this directory exists others directories: | ||
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Pay attention that inside the .snapshot directories you can see the **state** of his/hers directory how it was at the time of **snaphot**, | Pay attention that inside the .snapshot directories you can see the **state** of his/hers directory how it was at the time of **snaphot**, | ||
</ | </ | ||
+ | |||
+ | ===== For Algo/ | ||
+ | ==== What ==== | ||
+ | In this case, we use a standard linux file server (which costs 10 times less then the NetApp) and an home-brewed snapshot solution developed using standard Unix hard-links and the [[http:// | ||
+ | For the moment we take hourly snapshots and we keep 10 snapshots distributed logarithmically in time so that we have many recent snapshots and few old ones. The distribution over time is not regular because only meaningful snapshots (when something actually changed) are kept. Snapshots are only taken during the day, and from Monday to Friday. | ||
+ | Note also that sometimes for the snapshot system is down for maintenance, | ||
+ | |||
+ | ==== How ==== | ||
+ | Snapshots are presently only accessible only from linux workstations using the // | ||
+ | [root@algosrv5 bhome]# ls -1 / | ||
+ | < | ||
+ | 2007-09-20_Thu_14h | ||
+ | 2007-09-20_Thu_13h | ||
+ | 2007-09-20_Thu_12h | ||
+ | 2007-09-20_Thu_08h | ||
+ | 2007-09-19_Wed_12h | ||
+ | 2007-09-17_Mon_09h | ||
+ | 2007-09-10_Mon_12h | ||
+ | 2007-08-21_Tue_ 6h ~ 1 month ago | ||
+ | 2007-06-21_Thu_12h | ||
+ | </ | ||
+ | |||
+ | Snapshot directories are mounted '' | ||
+ | |||
+ |
backup/snapshot.txt · Last modified: 2015/07/01 15:42 by 127.0.0.1