SMF Network Services and the NWAM Process

To support “auto-magic” configuration of the network, the svc:/network/physical:nwam SMF instance was introduced in the initial NWAM implementation.

In the current NWAM implementation, the following SMF services have been added:

• network/netcfg:default

  This service is a prerequisite for the network/physical:nwam service. The service manages the network configuration repository, with its primary function being to start the netcfgd daemon. No configuration or modification of the service is required.

• network/location:default

  This service is dependent on the network/physical:nwam service and is responsible for activating the Location profile that is selected by the nwamd daemon.

  ---

  Note - The network/location:default service has a property that stores the current Location profile. Do not directly manipulate this property. Rather, use the NWAM GUI or the CLI to make these types of changes.

  ---

In Oracle Solaris, network configuration is implemented by multiple SMF services:

• svc:/network/loopback – Creates the IPv4 and IPv6 loopback interfaces. This service is unchanged in the current NWAM implementation.

• svc:/network/physical:default – Brings up links and plumbs IP interfaces.

  This service is disabled when the NWAM instance is enabled. To manually configure your network, or to use advanced networking features that are not currently supported by NWAM, for example IPMP and VNICs, you must first disable the network/physical:nwam service and then enable the network/physical:default service.

• svc:/network/initial – Loads the initial configuration for the various network subsystems and sets some global TCP parameters. This service is unchanged in the current NWAM implementation.

• svc:/network/service – Performs name service configuration that is dependent upon the availability of the DHCP lease.

  To enable more appropriate dependencies to be established and to provide more flexibility for different network policy engines to manage the service configuration, the svc:/network/service service has been split into three different services:

  • network/netmask – Resets the netmask and broadcast address, in the event that any new information from NIS is available.

  • network/ipqos – Loads IPQoS.

  • network/service – Updates the /etc/resolv.conf and /etc/nsswitch.conf files when the network/physical:nwam service is disabled, the network/physical:default service is enabled, and the network is manually configured.

    Note that when NWAM is enabled, the network/physical:nwam service handles updates to these files, enabling a better response to changes in the network environment, which also involve changes to the DHCP lease.

  These modifications are not a direct part of NWAM. However, the modifications provide for an easier transition to a more dynamic network configuration by enabling the restart and refresh of specific services without causing problems that might occur when a variety tasks are being performed simultaneously.

  Each new service includes a subset of the current set of dependencies for the network/services service. The network/netmask service is dependent on NIS services and the network/initial service. The network/ipqos service is dependent on the network/initial service and the file system services.

Refresh and Restart Behavior of the NWAM Service

Stopping the network/physical:nwam service has the same effect as shutting down the system's network capabilities. This task is accomplished by tearing down all interfaces and links and restoring the saved legacy network settings.

This reset behavior is accomplished by performing certain actions during the normal start and stop of the NWAM service. On startup, the nwamd demon determines if a hard reset or a soft reset should be performed. The reset type depends on the existence of the /etc/svc/volatile/nwam/nwamd_soft_reset file. For a soft reset, the current NCP is activated, thereby making any necessary changes to the link and interface configuration, so that the configuration matches the NCP.

Upon startup, the daemon performs the following steps:

1. If the Legacy location does not exist, the daemon creates the location, based on current settings

2. Tears down any configured links or interfaces

3. Activated the NoNet location

4. Activates the current NCP

5. Activates the appropriate Location profile after an interface becomes active

Upon normal shutdown, the nwamd daemon performs the following steps:

1. Tears down the current NCP

2. Activates the saved Legacy location settings