Network Detect

The Network Detect plugin is a simple device/module/interface that pings "virtual devices" to see if they are alive.
To enable the module, select under the Interfaces menu "Network Detect":

From DomotiGa 1.0.020 this plugin also supports arp-scan.

For first time usage it is smart to enable Debug apart from "Module Enabled".

Ping

Enabling devices to be pinged

To have a device, or better said, address to be pinged, you should add an device of the type "Ping" with interface "Network Interface":

Select the Type of the device to the "Ping" and the Interface will be automatically set to "Network Interface".
Under IP Addr. fill in the IP address or host name of the device you want to ping.

For the Ping Device field there are three options:
Device Status Ping successful Ping failure
Network Device Status On/Off On Off
Network Host Status Up/Down Up Down
Sony AIBO Status AIBO Awake Sleeping

Values

Two values are "returned":
  • value 1, "status", can be Up/Down, On/Off or Awake/Sleeping, see above
  • value 2 is giving the average ping value that is read from the output of ping:
    $ ping -c2 172.20.0.1
    PING 172.20.0.1 (172.20.0.1) 56(84) bytes of data.
    64 bytes from 172.20.0.1: icmp_req=1 ttl=64 time=0.681 ms
    64 bytes from 172.20.0.1: icmp_req=2 ttl=64 time=0.505 ms
    
    --- 172.20.0.1 ping statistics ---
    2 packets transmitted, 2 received, 0% packet loss, time 1001ms
    rtt min/avg/max/mdev = 0.505/0.593/0.681/0.088 ms
    
    Here value 2 will be 0.593

The status can be used in Events as trigger. You could for instance send an email if a goes down or even power cycle the host.
The average ping value can be used to plot the average ping time using the RRDTool module. For this, see Adding a graphs for a device value.

Arp-Scan

If you have enabled Arp-Scan, the plugin does a local network scan to see which arp request are answered, it then looks for all devices in the database which are of type Arp-Scan and check if they are found in the arp-scan output, if so their status is set to, Up, On, Home depending on devicetype.

To use arp-scan you have to install the command package, and allow normal users to run it as root by settings the 'sticky bit'

sudo apt-get install arp-scan
sudo chmod +s /usr/bin/arp-scan

Note: Arp-Scan can only be used for local networks, no mS time is returned, so it's just there or not there.

For the Arp-Scan Device field there are three options:
Device Status Scan successful Scan failure
Network Device Arp-Scan Status On/Off On Off
Network Host Arp-Scan Status Up/Down Up Down
Mobile Device Arp-Scan Status Home/Away Home Away

Debug

  • Enable Debug for Devices: Setup -> Main, activate the Devices checkbox
  • Enable Debug for Network Ping, see above
  • Wait for a while and open the debug log
  • You should see every 300 seconds (5 minutes) something like:
    2014/07/26 12:07:24 [Devices] Interface with name 'Ping Socket' has id '5'
    2014/07/26 12:07:24 [Ping] Checking 'router' with address '172.20.0.1'.
    2014/07/26 12:07:25 [Devices] ValueUpdate called for device with id '77' valuenum '2' and value '0.552'
    2014/07/26 12:07:25 [Devices] Device change triggered for device with id '77' and value2 '0.552'
    2014/07/26 13:07:25 [Ping] Device with id '77' is 'Up'.
    
  • If you do not see the first line, Network Ping is not enabled
  • If you do not see lines with [Ping], no Ping socket devices are enabled, see above how to add them

Related Resources

    Updated by: rdnzl, Updated over 2 years ago
    Access count: 44004

    network-detect.png (22.3 KB) rdnzl, 12/27/2014 04:46 PM

    network-ping.png (45.8 KB) rdnzl, 12/27/2014 04:56 PM

    mobile-scan.png (55.9 KB) rdnzl, 12/27/2014 04:56 PM

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