node-red-nodes/io/ping/README.md

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node-red-node-ping
==================
A <a href="http://nodered.org" target="_new">Node-RED</a> node to ping a
remote server, for use as a keep-alive check.
Install
-------
Either use the Editor - Menu - Manage Palette - Import option or run the following command in your Node-RED user directory - typically `~/.node-red`
npm install node-red-node-ping
**Gotchas**
1 Ubuntu Snap containers are strict and do not like giving external commands (like ping) external access. To allow ping to work you must manually add the network-observe interface
sudo snap connect node-red:network-observe
2 On some versions on Raspbian (Raspberry Pi) `ping` seems to be a root only command.
The fix is to allow it as follows
sudo setcap cap_net_raw=ep /bin/ping
sudo setcap cap_net_raw=ep /bin/ping6
Usage
-----
Pings a machine and returns the trip time in mS as `msg.payload`.
Returns boolean `false` if no response received, or if the host is unresolveable.
`msg.error` will contain any error message if necessary.
`msg.topic` contains the ip address of the target host.
Default ping is every 20 seconds but can be configured.