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--- mobi_backup [26.09.2018 15:50] – [Error due to old flock version] Pascal Suter
+++ mobi_backup [21.01.2019 12:58] – Pascal Suter
@@ Line 6: / Line 6: @@
 In most cases, this proves to be simple but still efficient enough, rather than trying block-level incrementals.
-at the end of a successful backup, a rotation is made and old backups are being deleted where appropriate. also a summary email is sent to the admin.
+One specialty of MOBI, and the main reason for writing this script in the first place, is that it runs multiple backups in parallel. It has sort of its own queue manager to do that. It will take all Job Definitions and put them in the queue and it will then run multiple in parallel. The number of parallel backup processes can be defined by setting the ''PARALLELPROCS=8'' variable in the script. Default is ''8''.
-so here is the script.. use it at your own risk and let me know if you find bugs or have contributions to make. simply send me an email to contact at psuter dot ch.
+The advantage of running multiple backup jobs at once is, that you can usually reach a much higher overall throughput with multiple rsyncs running in parallel than running them one after the other because rsync is single threaded and the overhead for ssh and file checking etc. is huge. So it usually makes no sense to wait for one host to complete before backing up a second host. \\
+You could also define multiple backup jobs for the same host but different directories on the host, to increase the speed of large backups.
+if you are looking for a solution to speed up an rsync copy process with parallel rsync invocations, take a look at my [[parallel_rsync]] article. Sadly the function I wrote there does not help in speeding up incremental backups at all (in contrary, it adds more overhead and hence makes an incremental backup even slower!).
+at the end of a successful backup, a rotation is made and old backups are being deleted where appropriate. also a summary email is sent to the admin.
 to configure, simply edit the lines or add more blocks after the
@@ Line 18: / Line 23: @@
 the script will write a hidden file named .lastdst to the backup base directory for each backup job. this file always contains the folder name of the sub directory of the last successful backup.
+so here is the script.. use it at your own risk and let me know if you find bugs or have contributions to make. simply send me an email to contact at psuter dot ch.
 <code bash mobi.sh>
@@ Line 335: / Line 342: @@
 rm -f /tmp/backupReport.txt
 </code>
+===== run daily =====
+in order to run the backup daily, run ''crontab -e'' as user ''root'' and enter a new line like this one here:
+1 * * * /opt/mobi.sh > /dev/null 2>&1
+using the redirects of both stdout and stderr to ''/dev/null'' makes sure you don't receive two emails on every backup where one would come through cron. all the necessary info is logged and the summary is emailaed directly without needing cron to send us any info.
 ===== Error due to old flock version =====
 when this script is run on an older linux distribution such as CentOS 6.5 for example, the provided version of flock is too old to know the ''-E'' option which specifies an exit code in case the lock could not be acquired. in such a situation you can patch the mobi.sh script using this command: