44 lines
1.5 KiB
Markdown
44 lines
1.5 KiB
Markdown
node-red-node-ping
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==================
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A <a href="http://nodered.org" target="_new">Node-RED</a> node to ping a
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remote server, for use as a keep-alive check.
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Install
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-------
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Either use the Editor - Menu - Manage Palette - Import option or run the following command in your Node-RED user directory - typically `~/.node-red`
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npm install node-red-node-ping
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**Gotchas**
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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
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sudo snap connect node-red:network-observe
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2 On some versions on Raspbian (Raspberry Pi) `ping` seems to be a root only command.
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The fix is to allow it as follows
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sudo setcap cap_net_raw=ep /bin/ping
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sudo setcap cap_net_raw=ep /bin/ping6
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Usage
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-----
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Pings 1 or more devices and returns the trip time in mS as `msg.payload`.
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Returns boolean `false` if no response received, or if the host is unresolveable.
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`msg.error` will contain any error message if necessary.
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`msg.topic` contains the ip address of the target host.
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There are 2 modes - `Timed` and `Triggered`.
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* 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.
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* 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.
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Refer to the built in help on the side-bar info panel for more details.
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