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77021aa1ce
Ticket: CM-10857 Reviewed By: julien, nikhil Testing Done: Tested moving from a dhcp to static addr method for eth0 before the patch: - when moving from dhcp to static address method, after releasing the dhcp address, it takes a few seconds for the dhcp address to go away. When we query addresses to configure, there is a chance that we may end up getting the dhcp address for a few seconds. Which is ok until when the static address to be configured is same as the dhcp address. In which case we end up not configuring the static address because we think it is already configured (per the running list). After this patch: - when moving from dhcp to static address method, we always re-apply the address config avoiding the chance of not configuring an address due to a dhcp address sticking around. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
python-ifupdown2
================
This package is a replacement for the debian ifupdown package.
It is ifupdown re-written in python. It maintains the original ifupdown
pluggable architecture and extends it further.
The python-ifupdown2 package provides the infrastructure for
parsing /etc/network/interfaces file, loading, scheduling and state
management of interfaces.
It dynamically loads python modules from /usr/share/ifupdownmodules (provided
by the python-ifupdown2-addons package). To remain compatible with other
packages that depend on ifupdown, it also executes scripts under /etc/network/.
To make the transition smoother, a python module under
/usr/share/ifupdownmodules will override a script by the same name under
/etc/network/.
It publishes an interface object which is passed to all loadble python
modules. For more details on adding a addon module, see the section on
adding python modules.
pluggable python modules:
=========================
Unlike original ifupdown, all interface configuration is moved to external
python modules. That includes inet, inet6 and dhcp configurations.
A set of default modules are provided by the python-ifupdown2-addons deb.
python-ifupdown2 expects a few things from the pluggable modules:
- the module should implement a class by the same name
- the interface object (class iface) and the operation to be performed is
passed to the modules
- the python addon class should provide a few methods:
- run() : method to configure the interface.
- get_ops() : must return a list of operations it supports.
eg: 'pre-up', 'post-down'
- get_dependent_ifacenames() : must return a list of interfaces the
interface is dependent on. This is used to build the dependency list
for sorting and executing interfaces in dependency order.
- if the module supports -r option to ifquery, ie ability to construct the
ifaceobj from running state, it can optionally implement the
get_dependent_ifacenames_running() method, to return the list of
dependent interfaces derived from running state of the interface.
This is different from get_dependent_ifacenames() where the dependent
interfaces are derived from the interfaces config file (provided by the
user).
Example: Address handling module /usr/share/ifupdownaddons/address.py
build
=====
- get source
- install build dependencies:
apt-get install python-stdeb
apt-get install python-docutils
- cd <python-ifupdown2 sourcedir> && ./build.sh
(generates python-ifupdown2-<ver>.deb)
install
=======
- remove existing ifupdown package
dpkg -r ifupdown
- install python-ifupdown2 using `dpkg -i`
- or install from deb
dpkg -i python-ifupdown2-<ver>.deb
- note that python-ifupdown2 requires python-ifupdown2-addons package to
function. And python-ifupdown2-addons deb has an install dependency on
python-ifupdown2