Netgwm Save

NetGWM stands for Network Gateway Manager (http://flant.ru/projects/netgwm)

NetGWM is a tool on Python used for automatically switching network gateway when your current ISP goes offline.

How to deploy NetGWM? 0) Install prerequisites:

• iproute2
• conntrack (http://conntrack-tools.netfilter.org/)
• python-yaml (http://pyyaml.org/)

1. Execute "make install". It will create /usr/lib/netgwm with netgwm.py and /etc/netgwm with configs and samples.
2. Using simple YAML configuration file (samples/netgwm.yml), you should define your gateways (by IPs or devices) and their priorities. In /etc/default/netgwm, you can change the period of checking gateways (by default, every 60 sec).
3. Add new routing table named "netgwm_check" to your iproute configuration file (/etc/iproute2/rt_tables; there is an example at samples/rt_tables.sample). It's done automatically in the Debian package.
4. Use /etc/init.d/netgwm to launch NetGWM.

That's all! NetGWM will ping given addresses through your current gateway to check your Internet connection. If all of these addresses are down, NetGWM will switch your current gateway to a working one (with a highest priority).

Other features:

• A gateway is considered as working only after N seconds of successfull checks. This setting ("min_uptime") can be configured in netgwm.yml.
• When a gateway with a higher priority goes back online NetGWM will automatically switch to it from the current one.
• Every time NetGWM switches a network gateway, it will execute all the scripts placed in /etc/netgwm/post-replace.d (for more details, please have a look at samples/post-replace.d/script.sh).
• NetGWM can maintain the full list of gateways statuses continually for your special needs (e.g. to be used in other software). This data is stored in /var/run/netgwm/gwstore.yml. This setting ("check_all_gateways") can be enabled in netgwm.yml.