Pekka Helenius 812cd6eaf1 | 6 years ago | |
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images | 6 years ago | |
README.md | 6 years ago | |
wanip-checker.sh | 6 years ago | |
wanip-checker@.service | 6 years ago |
WAN IPv4 checker & email notifier for server environments behind dynamic DHCP.
This repository contains a systemd service file & a simple bash script to refresh current WAN IPv4 of a server, and notify server admin for any changes in the server WAN (Internet) address. This helps in several issues:
Server admin is always aware of the current server IPv4 address, whether the address is dynamic or not.
Server admin is able to remotely connect to the server environment although the server IP may have been changed. This is possible because the admin is notified about any WAN IPv4 address changes via email by the server itself, automatically.
In many home networks, WAN (Wide Area Network) IP addresses are dynamically allocated by a local ISP. Usually this is okay in common household/home use, but not in server use.
In most server environments, static DHCP lease/static IP address is a mandatory requirement. However, static IPs are usually offered only for corporate environments, and not everyone wants to pay extra for such in order to establish a simple server environment in home.
A server computer of any kind
Linux OS
systemd - service file
SSMTP - email client
bash
awk
systemd user service file: wanip-checker@.service
bash script: wanip-checker.sh
1) Insert wanip-checker@.service
into /usr/lib/systemd/user/
folder
60
(1 min)2) Insert wanip-checker.sh
into your /home/myuser/
folder
3) Configure your email address and message form in wanip-checker.sh
file
3) Install ssmtp
, and configure files /etc/ssmtp/revaliases
and /etc/ssmtp/ssmtp.conf
as described on SSMTP Arch Wiki site.
4) Run
systemctl --user enable wanip-checker@myusername.service && \
systemctl --user start wanip-checker@myusername.service && \
systemctl --user daemon-reload
NOTE: If you change the script contents, make sure to run systemctl --user restart wanip-checker@myusername.service
afterwards.
When server computer discovers changes in WAN IPv4, it automatically sends an email notification for system administrators:
Additionally, server computer keeps a log file which include WAN IPv4 changes and corresponding timestamps: