Jean-Louis, It's getting complicated, because in my previous post below I reported that with option "--atime-preserve=system" a level 1 tar incremental worked. However, some time later it didn't work any more, so it is really "unpredictable".
I have repeated part of below with some stat in between. Results are in attachment tar_1.26_incremental. It seems that in the first create tar changes atime. Because I got no good results so far, I have installed the latest 1.27 tar from gnu, which is in /usr/local/bin and repeated the results from above. With 1.27 no times are changed at level 0 or level 1. Results in attachment tar_1.27_incremental. Both tests actually did (now) a proper incremental tar as can be seen from the the size of the created files: -rw-r--r-- 1 charles users 379238400 Feb 25 17:23 wine_docs_0.tar -rw-r--r-- 1 charles users 71680 Feb 25 17:24 wine_docs_1.tar -rw-r--r-- 1 charles users 13405 Feb 25 17:24 wine_docs.snar -rw-r--r-- 1 charles users 1785 Feb 25 17:28 tar_1.26_incremental -rw-r--r-- 1 charles users 379238400 Feb 25 17:36 wine_docs_0_1.27.tar -rw-r--r-- 1 charles users 71680 Feb 25 17:36 wine_docs_1_1.27.tar -rw-r--r-- 1 charles users 13405 Feb 25 17:36 wine_docs_1.27.snar -rw-r--r-- 1 charles users 2100 Feb 25 17:39 tar_1.27_incremental I am now continuing with amanda, but testing takes much longer. But my best bet now is to use 1.27 and I will use amgtar to do achieve that. Regards, Charles On Tue, 25 Feb 2014 09:50:00 -0500 Jean-Louis Martineau <martin...@zmanda.com> wrote: > Charles, > > Can you post the output of the 'stat' command of one of the file > before the level 1 backup and after the the level 1 backup, to see > what changed. > > Jean-Louis > > On 02/25/2014 04:53 AM, Charles Stroom wrote: > > I am now just testing tar, without amanda and I get the following > > results (just following the gnu doc): > > > > charles@fiume:~> tar --create --file=/tmp/wine_docs_0.tar > > --listed-incremental=/tmp/wine_docs.snar wine_docs/ > > charles@fiume:~> ll -tr /tmp > > .. > > -rw-r--r-- 1 charles users 379944960 Feb 25 10:27 wine_docs_0.tar > > -rw-r--r-- 1 charles users 13405 Feb 25 10:27 wine_docs.snar > > charles@fiume:~> du -sk wine_docs/ > > 371500 wine_docs/ > > > > charles@fiume:~> cd wine_docs/ > > charles@fiume:~/wine_docs> touch spreadsheets/* viacad/Drawings/* > > badkamer/ > > > > charles@fiume:~/wine_docs> cd .. > > charles@fiume:~> tar --create --file=/tmp/wine_docs_1.tar > > --listed-incremental=/tmp/wine_docs.snar wine_docs/ > > charles@fiume:~> ll -tr /tmp > > .. > > -rw-r--r-- 1 charles users 379944960 Feb 25 10:27 wine_docs_0.tar > > -rw-r--r-- 1 charles users 379944960 Feb 25 10:30 wine_docs_1.tar > > -rw-r--r-- 1 charles users 13404 Feb 25 10:30 wine_docs.snar > > > > Et voila -> a "full" incremental backup. > > > > I than repeated the whole sequence, with the > > "--atime-preserve=replace" added, and there is no change: again > > "full" incremental backup. > > > > And than again but now with "--atime-preserve=system" and now this > > works! > > > > charles@fiume:~> tar --create --file=/tmp/wine_docs_0.tar > > --listed-incrementaltmp/wine_docs.snar --atime-preserve=system > > wine_docs/ charles@fiume:~> touch wine_docs/output.p* > > wine_docs/spreadsheets/* charles@fiume:~> tar --create > > --file=/tmp/wine_docs_1.tar --listed-incrementaltmp/wine_docs.snar > > --atime-preserve=system wine_docs/ charles@fiume:~> ll -tr /tmp | > > tail -3 -rw-r--r-- 1 charles users 379944960 Feb 25 10:44 > > wine_docs_0.tar -rw-r--r-- 1 charles users 13404 Feb 25 10:45 > > wine_docs.snar -rw-r--r-- 1 charles users 512000 Feb 25 10:45 > > wine_docs_1.tar charles@fiume:~> tar --create > > --file=/tmp/wine_docs_2.tar --listed-incrementaltmp/wine_docs.snar > > --atime-preserve=system wine_docs/ charles@fiume:~> ll -tr /tmp | > > tail -4 -rw-r--r-- 1 charles users 379944960 Feb 25 10:44 > > wine_docs_0.tar -rw-r--r-- 1 charles users 512000 Feb 25 10:45 > > wine_docs_1.tar -rw-r--r-- 1 charles users 112640 Feb 25 10:47 > > wine_docs_2.tar -rw-r--r-- 1 charles users 13405 Feb 25 10:47 > > wine_docs.snar > > > > Moreover, I checked the contents of the incremental tars, and they > > contained the full directory structure plus only the touched files > > (in the last case, actually none). > > > > Is there an easy way to get this option added to tar in amanda, or > > do I need to recompile? > > > > > > Regards, Charles with many thanks for the pointers received. > > > > > > > -- Charles Stroom email: charles at no-spam.stremen.xs4all.nl (remove the "no-spam.")
tar_1.26_incremental
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tar_1.27_incremental
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