The usage of ipassign is as follows:
There are four windows.
MainWindow is the application entry point, on which a list of discovered
icepaps is displayed.
There are two properties windows, a simpler HostnameWindow where the hostname
can be set, and a more advanced NetworkWindow in which ip setting can also be
configured. By default, HostnameWindow is displayed.
LogWindow displays a log of the traffic on the network.
This window is the user's entry point into the application.
It is responsible for discovery requests.
When launched, the application will send a discovery packet to find devices on
the network. This action can be repeated by clicking Refresh.
Available devices are sorted by hostname in the central list.
Clicking either on an entry in the list or on Properties will display its
properties.
HostnameWindow sets a device's configuration from its hostname, by performing look-ups. Configuring network settings by hostname is the most common operation, and is passign's default mode of operation.
The hostname is validated with respect to RFC 1123, section 2.1. If the
hostname is not valid, the Apply button is disabled.
If found in DNS, the hostname and its network settings will be written to flash
and applied dynamically.
These settings are found by networking.from_hostname.
The Advanced push-button allows to switch to the NetworkWindow view.
NetworkWindow allows the setting of all of a device's network settings.
These are Hostname, IP settings, and whether to apply these settings dynamically, to write them to flash, or reboot.
Alternatively, it is also possible to query the DNS and set these as values to apply.
The configuration given at the moment of drawing the window is kept
within self._config. The new configuration will only be created when
Apply is clicked.
The Reset button resets the fields with the values previously obtained from
the device (passed to the window upon drawing), that is stored in self._config.
Within NetworkWindow, IP address fields are validated using
ipaddress.IPv4Address.
As with HostnameWindow, the hostname is validated against RFC 1123.
If any field is invalid, Apply will be disabled.
Once Apply is clicked, IPs are verified to be in range of one another within
the netmask. If all is valid, then the configuration will be updated and sent
to the network via NetworkInferface.send_configuration.
Clicking Simple Mode switches back to HostnameWindow.
A log of the traffic on the network and actions within ipassign can be viewed
in LogWindow.
This window contains a read-only text field that, when displayed refreshes
automatically.
From the log window, it is possible to save these to file.
All the networking is handled by networking.NetworkInterface. This object has
the two methods do_discovery and send_configuration.
An instance is automatically created when importing the file, as a poor-man's
singleton.
Messages to and from ipassign always have the mac address 00:D1:5E:A5:ED:00.
The socket times out on input messages after 200 ms. This was experimentally chosen as a decent value. Perhaps a lesser value could work, but would create issues in networks with more devices (eg. on awaiting configuration acknowledgements).