Dia antes primera install

node_modules/node-red-node-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 1 or more devices 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.
+
+There are 2 modes - `Timed` and `Triggered`.
+
+* Timed mode - this is the default mode that pings your devices on a timed basis. Default ping is every 20 seconds but can be configured.
+* Triggered mode - this mode permits you to trigger the ping by an input message. If the `Target` is left blank and `msg.payload` is a string or array, you can ping 1 or more devices on demand.
+
+Refer to the built in help on the side-bar info panel for more details.