Introduction to network interface helper

You can use the net_helper set of tools when setting up network interfaces upon a new installation. For more details and examples, see 8.  Network interfaces.

About

There are many ways to configure a set of network interfaces. The main goal of these tools is to provide an easy way to define an end configuration state, then generate or cleanup/re-generate the network configuration based on this end state kept persistently.

An example initial configuration includes the following:

  • Physical interfaces to be used for the storage and iSCSI services.

  • IP networks for both the storage and the iSCSI services.

  • VLANs for the storage network, additional VLANs for iSCSI and other purposes.

  • Network topology type for storage/iSCSI, based on known-good pre-defined choices.

This configuration could be used to generate interfaces, and their addresses based on the provided sp-network, concatenated with the SP_OURID on each of the nodes and any offset if provided (net_helper genconfig). Another option is to construct all IP addresses manually, and then apply with net_helper applyifcfg.

A secondary goal is to provide rapid re-generation of network configurations for all supported operating systems and network configurations we see in production for our internal testing.

How it works

There are a few ways to provide configuration details:

  • Automatically generate addresses (based on the node’s SP_OURID):

    • From ansible to provide necessary parameters for net_helper genconfig.

    • Directly by using net_helper genconfig on a node.

  • Manually constructing a configuration (perhaps based on the provided by genconfig)

  • Using net_helper applyifcfg directly, and providing all details as arguments.

Use cases

The primary use case for these instruments is to provide reproducible networking configuration, by gluing all internally used tools for configuring the network by exposing all relevant options to the ansible configuration, and providing idempotency for networking configuration.

History

This feature is available starting with release 19.4 revision 19.01.3061.a03558598.