From fb95cef5b8e9b42c617e78bb999f53ccb45191f0 Mon Sep 17 00:00:00 2001 From: Holger Frey Date: Fri, 9 Aug 2019 14:58:18 +0200 Subject: [PATCH] updated readme --- README.md | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/README.md b/README.md index 77c13a8..9038483 100644 --- a/README.md +++ b/README.md @@ -44,3 +44,19 @@ https://wiki.cpi.imtek.uni-freiburg.de/CPIvServerDocumentation/ElabOnZfs rm tmp-backup-file.gz ``` + +## notes on implementation ## + +At first I tried to implement the complete process in one python file, but this +lead to an unforseen (and very strange) error: + +The created gzip file was not completely written before copying it to the remote +server. Even closing the file descriptor manually or waiting for a very long +time would not solve the problem. The gzip was only completed if the python +process was stopped. + +Therefore creating the backups and copying them to the remote server is now a +two step process, combined in the `run_snapshot_backups.sh` shell script. + +I have the idea, that it has todo with the copy on write feature of zfs, but +I'm not sure about it.