[fix] add workaround to manage backup

Needed while waiting for a solution. See https://github.com/YunoHost/issues/issues/1266

backup.md

@@ -78,8 +78,15 @@ scp /path/to/your/<archivename>.tar.gz admin@your.domain.tld:/home/yunohost.back
 
 Alternatively, a solution can be to install Nextcloud or a similar app and configure it to be able to access files in `/home/yunohost.backup/archives/` from a web browser.
 
-Restoring backups
------------------
+### Workaround to retrieve the backups
+
+<div class="alert alert-danger">
+  <span class="glyphicon glyphicon-exclamation-sign"></span> Since Yunohost version 3.3 and the choice to connect as the `admin` user, there is a [limitation](https://github.com/YunoHost/issues/issues/1266) that prevents straight access to the backups folder `/home/yunohost.backup/archives/`
+</div>
+
+Until the issue is solved, you will need to follow [a workaround](/backup_workaround) to manage the backup files.
+
+## Restoring backups
 
 ### From the webadmin
 

backup_workaround.md

@@ -0,0 +1,140 @@
+# Workaround to retrieve the backups
+
+As said on the [backup](/backup), there is a limitation to manage backups files with `admin` user
+
+## What is the problem
+
+Why you cannot access to `/home/yunohost.backup/archives/` folder
+
+```bash
+root@example:~# tree /home/yunohost.backup/
+/home/yunohost.backup/
+├── archives                          ## <== Only `root` can access
+│   ├── 20180611-192934.info.json
+│   ├── 20180611-192934.tar.gz
+│   ├── 20180915-212428.info.json
+│   ├── 20180915-212428.tar.gz
+│   ├── wallabag2-pre-upgrade1.info.json
+│   └── wallabag2-pre-upgrade1.tar.gz
+└── tmp                               ## <== `admin` can write here
+    ├── 20180915-212428.info.json
+    └── 20180915-212428.tar.gz
+
+2 directories, 8 files
+root@example:~#
+```
+
+Until it is sorted, you have to work with `/home/yunohost.backup/tmp` and then copy/move to `home/yunohost.backup/archives` so Yunohost backup system can do it's work.
+
+## Download backups
+
+You will need to connect by `SSH` to copy the backups to a location that can be acceded by the `admin` user
+
+### SSH connection
+
+1. Connect by following [SSH instructions](/ssh#after-installing-yunohost)
+
+    ```bash
+    ssh admin@192.168.1.68
+    admin@192.168.1.68's password:
+
+    The programs included with the Debian GNU/Linux system are free software;
+    the exact distribution terms for each program are described in the
+    individual files in /usr/share/doc/*/copyright.
+
+    Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
+    permitted by applicable law.
+    Last login: Sun Jan  6 19:30:47 2019 from 192.168.1.51
+    ```
+
+2. Verify if `admin` can access backups
+
+    ```bash
+    admin@example:~$ ls -l /home/yunohost.backup/archives/
+    ls: cannot open directory /home/yunohost.backup/archives/: Permission denied
+    ```
+
+3. Run the same command again with `sudo` to list backups
+
+    ```bash
+    admin@example:~$ sudo ls -l /home/yunohost.backup/archives/
+    total 1168888
+    -rw------- 1 admin 1007      3427 Jun 17  2018 20180611-192934.info.json
+    -rw------- 1 admin 1007 592976408 Jun 17  2018 20180611-192934.tar.gz
+    -rw-r--r-- 1 root  root      1436 Sep 15 21:25 20180915-212428.info.json
+    -rw-r--r-- 1 root  root 164731292 Sep 15 21:25 20180915-212428.tar.gz
+    -rw-r--r-- 1 root  root       331 Dec 31 12:10 dokuwiki--2-pre-upgrade1.info.json
+    -rw-r--r-- 1 root  root     23800 Dec 31 12:10 dokuwiki--2-pre-upgrade1.tar.gz
+    -rw-r--r-- 1 root  root       348 Dec 31 12:10 dokuwiki--3-pre-upgrade2.info.json
+    -rw-r--r-- 1 root  root   3710604 Dec 31 12:10 dokuwiki--3-pre-upgrade2.tar.gz
+    -rw-r--r-- 1 root  root       344 Dec 31 12:08 dokuwiki-pre-upgrade2.info.json
+    -rw-r--r-- 1 root  root 163209554 Dec 31 12:08 dokuwiki-pre-upgrade2.tar.gz
+    admin@example:~$
+    ```
+
+    The most recent backup in this example is from `20180915-212428`. It is going to be copied to the right location
+
+4. Login as superuser `root`
+
+    ```bash
+    admin@example:~$ sudo -i
+    ```
+
+5. Copy the previous backups files to `/home/yunohost.backup/tmp`
+
+    ```bash
+    root@example:~# cd /home/yunohost.backup
+    root@example:~# sudo cp -a archives/<archivename>* tmp
+    ```
+
+6. Verify that you have two files `<archivename>`.info.json and `<archivename>`.tar.gz in `/home/yunohost.backup/tmp`
+
+    ```bash
+    root@example:~# ls /home/yunohost.backup/tmp
+    20180915-212428.info.json  20180915-212428.tar.gz
+    ```
+
+7. Quit SSH connection
+
+    ```bash
+    root@example:~# exit
+    admin@example:~$ exit
+    ```
+
+## Upload backups
+
+If you want to restore backup, the steps are quite similar to above.
+
+1. Connect by following [SSH instructions](/ssh#after-installing-yunohost)
+
+2. Login as superuser `root`
+
+    ```bash
+    admin@example:~$ sudo -i
+    ```
+
+3. Move your backup `<archivename>` to `/home/yunohost.backup/archives`
+
+    ```bash
+    root@example:~# cd /home/yunohost.backup
+    root@example:~# mv tmp/`<archivename>*` archives/
+    ```
+    Yunohost backup mechanism can work do its work.
+
+4. Verify that you have two files `<archivename>`.info.json and `<archivename>`.tar.gz in `/home/yunohost.backup/archives`
+
+    ```bash
+    root@example:~# ls /home/yunohost.backup/archives
+    20180915-212428.info.json  20180915-212428.tar.gz
+    ```
+
+5. Quit SSH connection
+
+    ```bash
+    root@example:~# exit
+    admin@example:~$ exit
+    ```
+
+## Back to work
+
+Now that the files are in the correct folders, you can continue your work with the [backups](backup).