**1)** Insert `wanip-checker@.service` into `/usr/lib/systemd/user/` folder
**1)** Insert `wanchecker@.service` and `wanchecker@.timer` into `/usr/lib/systemd/user/` folder
- WAN IP check interval is customizable in systemd service file. Default value is `1200` (20 min)
- WAN IP check interval is customizable in systemd timer file. Default value is `20min`
**2)** Insert `wanip-checker.sh` into your `/home/myuser/` folder
**2)** Insert `wanchecker.sh` into your `/home/myuser/` folder (where `myuser` is your real username on your Linux system)
**3)** Configure your email address and message form in `wanip-checker.sh` file. In addition, configure WAN IPv4 log file location (default is `$HOME`)
**3)** Configure your email address and message form in `wanchecker.sh` file. In addition, configure WAN IPv4 log file location (default is `$HOME`)
- log file is updated only when WAN IPv4 changes have been detected
- log file is updated only when WAN IPv4 changes have been detected
**3)** Install `ssmtp`, and configure files `/etc/ssmtp/revaliases` and `/etc/ssmtp/ssmtp.conf` as described on [SSMTP Arch Wiki site](https://wiki.archlinux.org/index.php/SSMTP).