Differences

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--- backup:night [2007/05/26 19:43] – damir
+++ backup:night [2015/07/24 09:28] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 ====== Night Backup ======
-Currently we have 2 different process of nightly backups
+  * The process start around midnight and save the whole content of the Filer in another file server, accessible only to the System Administrators.
-  * The first process start around 22.00 and save, on digital tape, a copy of all the files changed during the day in the Filer (the file server where the homedirs are stored). Every Sunday, the process copies the whole content of the Filer, no matter when and if the files changed.
-  * The second process start around midnight and save the whole content of the Filer in another file server, accessible only to the System Administrators. In this case the copy is stored on hard disks.
 \\
-===== Backup on Tape =====
+==== HowTo recover =====
+In the process of recovery is quite simple and fast and the data needed can be accessible during the hour. For security reason the acces to this server is limited to the System Administrators, but a simple request is enough to obtaining the files needed. The cons is that the procedure of saving the complete Filer require a lot of time (around 3,5 Hours, today) and disk space (around 2.5 TByte now). For this reason we can guarantee access to only 30 days of backup.
-The use of digital tapes permit to maintain a very long history of the files of users. Thanks to the relative low cost of the tapes, we can have 4 months of backup. Unfortunately the tapes are difficult to manage and the access to the data is quite slow. This means that the recover of a single file require a lot of time.\\
+The presence of this backup is explained by the necessity to have a complete, simpler and and fast way to restore the content of Filer in case of complete crash of the system.
-The management of the tapes is done by the EPFL Backup Team and every request of recover must be pass from the System Administrator of the lab, that can forward the request to the responsable of backup. Normally the access to the data recovered is quaranted in the day of request.
-===== Backup on Disk =====
-In the second case the process of recover is quite simple and fast and the data needed can be accessible during the hour. For security reason the acces to this server is limited to the System Administrators, but a simple request is enough to obtaining the files needed. The cons is that the procedure of saving the complete Filer require a lot of time (around 3,5 Hours, today) and disk space (around 250 Gbyte for day now). For this reason we can guarantee access to only 5 days of backup.
-The presence of this backup is explained by the necessity to have a complete and fast way to restore the content of Filer in case of complete crash of the system.