Hello and welcome to this lecture and this lecture we discussed about IP address management.
So how does IP address management work and cobra.
Notice this section does not concern the IP address assigned to the nodes in the network.
We can manage that on your own or with your own external Pam solutions.
What this section covers is however the word tool brutes networks and the nodes assigned an IP subnet.
And how are the parts assigned an IP.
Where is this information stored and who is responsible for ensuring there are no duplicate IP is assigned.
Let's start with The Who.
Let's ask CNI as they're the ones who define the standards CNI says it is the responsibility of the
CNI plug in the network solution provider to take care of assigning IP to the containers.
Remember the basic plugin we built earlier.
We actually took care of assigning IP addresses within this plugin.
There was a section for assigning IP to the container network namespace.
But how do we manage these APIs competent is doesn't care how we do it.
We just need to do it by making sure we don't assign any duplicate APIs and manage it properly.
An easy way to do it is to store the list of APIs in a file and make sure we have necessary code in
our script to manage this file properly.
This file would be placed on each host and manages the APIs of parts on those notes instead of coding
that ourselves in our script CNI comes with two built in plugins to which you can outsource this task
to.
In this case the plugin that implements the approach that we followed for managing the IP addresses
locally on each host is the host local plugin but is still our responsibility to invoke that plugin
in our script or we can make our script dynamic to support different kinds of plugins.
The CNI configuration file has a section called APM in which we can specify the type of plug in to be
used the subnet and route to be used.
This details can be read from our script to invoke the appropriate plugin instead of hard coding it
to use hosted local every time different network solution providers does it differently.
Let's see how we works managers IP addresses.
In fact you have seen some of the APIs assigned by Reef in the previous practice test.
We've by default allocates the appearance tender to 0 0 0 slash twelve for the entire network.
That gives the network IP from range tender 32 of 0 1 to 10 not 47 not 255 but 254.
That's about a million APIs that you can use for part on the network from this range.
The peers decide to split the IP addresses equally between them and assigns one portion to each node
pods created.
On this note we'll have is in this range.
Of course these ranges are configurable with additional options past while deploying the weave plug
into a cluster.
Well for this lecture.
Head over to the practice test and explore a pan in the weave CNI plugin.