[Bacula-users] Rif: How does Bacula back-up files?

Hello Obviously.
Obviously this is a standard linux (unix) behaviour. If you open a file its inode is associated with one process fd and it does not need to use the filename written in the directoty.
When you erase the file (rm, I suppose), you simply cat the name off the directory list, but the open fd continues to work. On file close the OS realizes the the use comunt of the file went to 0 and phisically delete it from disk, reusing the space.
Some applications use this feature for temporary files, opening them ad deleting immediatly. If the application stops for whatever reason no garbage remain around.

Regards,

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Da: obviously <bacula-forum AT backupcentral DOT com>
Per: bacula-users AT lists.sourceforge DOT net
Data: 13/05/2011 14.48
Oggetto: [Bacula-users] How does Bacula back-up files?

Hello, I have a question I can't solve... The is the situation: I create a file with: dd if=/dev/urandom of=test.bin bs=10M count=300 This gives me a file of 3GB. I check it's MD5 with md5sum test.bin I clear my cache with echo 3 > /proc/sys/vm/drop_caches. I check my chache with free -m. I start a backup with Bacula of only 1 file, namely test.bin Again, I flush the cache and when the back-up job is starting I remove the test.bin file on the server. And Bacula doens't react at all, it keeps backing up the file like it is still there. The backup finishes with no warnings, even it is removed during the backup. I restore the test.bin file from tape and checks the md5 of it, and strangely the md5sum is the same... So my question, how does Bacula do this? Cause I remove the file during the backup and flush the cache frequently... I hope you guys understand my q, my english is realy bad :) excuse me... +---------------------------------------------------------------------- |This was sent by tijshooyberghs AT hotmail DOT com via Backup Central. |Forward SPAM to abuse AT backupcentral DOT com. +---------------------------------------------------------------------- ------------------------------------------------------------------------------ Achieve unprecedented app performance and reliability What every C/C++ and Fortran developer should know. Learn how Intel has extended the reach of its next-generation tools to help boost performance applications - inlcuding clusters.http://p.sf.net/sfu/intel-dev2devmay_______________________________________________ Bacula-users mailing list Bacula-users AT lists.sourceforge DOT nethttps://lists.sourceforge.net/lists/listinfo/bacula-users

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What every C/C++ and Fortran developer should know.
Learn how Intel has extended the reach of its next-generation tools
to help boost performance applications - inlcuding clusters.
http://p.sf.net/sfu/intel-dev2devmay

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