Backing up your data

Though you might use industrial storage solutions for the WebHMI, still there is always a risk of losing your data in some cases:

Just forget to make a copy of the project - this is the most common case. Backup files are created on local WebHMI storage for your convenience, but it's up to you to save the latest valuable changes on your PC or other storage.
Occasionally clear all collected data, e.g. when restoring your backup with unchecked “keep data” option
Flash drive wearing out
Abrupt power off during critical file operation (which you can not control) - on a virtual machine or WebHMI with a failed backup battery
Filesystem/DB operations failure, which still has a minor chance to happen. That's why RAID technologies exist.

There is only one example of how to avoid the consequences of data loss considered here. Using shell script via crontab utility.

Download all present logs once

At the very start, it is a good idea to download all the data.

backup-ALL.sh

#!/bin/bash
# Create a folder ~/webhmi-log-cron, with the /tmp sub-folder.
HOST=192.168.1.1
LOG_DIR="$HOME/webhmi-logs-backup"
mkdir -p $LOG_DIR/tmp
cd $LOG_DIR/tmp
 
# Get all logs (including today, which is, however, obviously partial)
wget --user=admin --password=webhmi -nH --cut-dirs=1 "ftp://$HOST/log/log*.sqlite3"
 
# Archive to save storage space
gzip -f -v *
# Copy out of tmp .gz file and do not overwrite if destination filename already exists
cp -r --backup=t log-*.sqlite3.gz ../.
# Clear tmp folder
rm $LOG_DIR/tmp/*

Crontab on Linux

Here is an example of how to set up your Linux machine to automatically save files from the /log folder on the WebHMI's storage:

backup.sh

#!/bin/bash
# Create a folder ~/webhmi-logs-backup, with the /tmp sub-folder.
HOST=192.168.1.1
LOG_DIR="$HOME/webhmi-logs-backup"
cd $LOG_DIR/tmp
# download yesterday's log file to backup storage
yesterday=$(date +"%Y-%m-%d" -d yesterday)
 
 
 
# because login and pass for the FTP connection are unencrypted you can 
# restrict read/write access mode to the file with chmod command)
wget --user=admin --password='webhmi' ftp://$HOST/log/log-$yesterday.sqlite3
#archive to save storage space
gzip -f -v log-$yesterday.sqlite3
# Copy out of tmp .gz file and do not overwrite if destination filename already exists
cp -r --backup=t log-$yesterday.sqlite3.gz ../.
# Clear tmp folder
rm $LOG_DIR/tmp/*

Do not forget to grant additional run permissions

chmod u+x /path_to_run/backup.sh

Add the script to the crontab with the parameters:

10 0 * * * /path_to_run/backup.sh

to run it every day at 00:10

New files will only be added to ~/WEBHMI/log_backup, nothing will be deleted from this folder.

WebHMI Docs

Table of Contents

Backing up your data

Download all present logs once

Crontab on Linux