Go to main content

Configuring and Managing Network Components in Oracle® Solaris 11.4

Exit Print View

Updated: December 2019

Customizing Datalink Properties

You can also use the dladm command to set datalink properties and customize them according to the requirements of your network.

The following three dladm subcommands are used to administer datalink properties. The properties you can customize depend on what the specific NIC driver supports.

dladm show-linkprop –p propertydatalink

Displays the properties of a datalink and its current values. If you do not use the –p property option, then all of the properties of the datalink are displayed. If you do not specify a datalink, then all of the properties for all of the datalinks are displayed.

dladm set-linkprop –p property=value datalink

Assigns a value to a datalink's property.

dladm reset-linkprop –p property datalink

Resets a specific property of a datalink to its default value.

    Datalink properties that are configurable by using the dladm command fall into one of two categories:

  • Public properties – Applicable to any driver of the given media type such as link speed, auto-negotiation for Ethernet, or the maximum transmission unit (MTU) size that can be applied to all datalink drivers.

  • Private properties – Specific to a subset of NIC drivers for a specific media type. These properties can be specific to that subset because they are closely related, either to the hardware that is associated with the driver or to the details of the driver implementation itself, such as debugging-related tunables.

Enabling Support for Jumbo Frames

The MTU property defines the size of the largest packet that a protocol can transmit from the system. By default, most NIC drivers define the MTU size to 1500. However, for Jumbo frames are traversing the network, the MTU size must be at least 9000.

Note -  The MTU property is common to both datalinks and IP interfaces, which means you can have one MTU value for a datalink and another MTU value for the IP interface that is configured over that link. The value of the datalink MTU impacts the possible values that you can set for an IP interface's MTU. For more information, see Setting the MTU Property.

The following example shows how to enable support for Jumbo frames. This example assumes that you have already removed any existing IP interface configuration over the datalink.

$ dladm show-linkprop -p mtu net1
net1     mtu             rw   1500         1500         1500      1500

$ dladm set-linkprop -p mtu=9000 net1
$ dladm show-link net1
web1     phys      9000     up        --         --

Modifying Link Speed Parameters

Most network setups include a combination of systems that have varying speed capabilities. These capabilities are usually specified in tandem with duplex settings, for example, full or half-duplex.

Each system advertises speed capabilities to other systems on the network to determine how each system is transmitting and receiving network traffic. Usually, systems use auto-negotiation to determine compatible speed and duplex settings. However, in some instances, it might be necessary to specify a given speed and duplex combination. In these instances, you can set the speed-duplex property for the specified datalink. Note that the speed-duplex property replaces the legacy en-speed-duplex-cap and adv-speed-duplex-cap properties (en1000fdx-cap) that were used in previous Oracle Solaris releases to set speed-duplex combinations and retrieve their current state, respectively.

    You can set the following values for the speed-duplex property:

  • 10g-f (10Gigabit full-duplex)

  • 1g-f (1Gigabit full-duplex)

  • 1g-h (1Gigabit half-duplex)

  • 100m-f (100Megabit full-duplex)

  • 100m-h (100Megabit half-duplex)

  • 100m-f (10Megabit full-duplex)

  • 10m-h (100Megabit half-duplex)

The following example shows how to specify 10Gigabit/1Gigabit full-duplex for a datalink:

$ dladm set-linkprop -p speed-duplex=10g-f,1g-f datalink

To display the new property values, type:

$ dladm show-linkprop -p speed-duplex datalink

Setting the STREAMS Module on Datalinks

You can set up to eight STREAMS modules to be pushed onto the stream when a datalink is opened. These modules are typically used by third-party networking software such as virtual private networks (VPNs) and firewalls. Documentation about this type of networking software is provided by the software vendor.

The list of modules to push on a specific datalink is controlled by the autopush property. You set the value of the autopush property by using the dladm set-linkprop command.

Modules are pushed on a per-link as well as per-driver basis. If both per-link and per-driver types for the autopush configuration exist for a datalink, the per-link information that is set with the dladm set-linkprop command is used, and the per-driver information is ignored.

The following example shows how to push the vpnmod and bufmod modules on top of the link net0 as follows:

$ dladm set-linkprop -p autopush=vpnmod.bufmod net0

Obtaining Status Information for Datalink Properties

    To obtain status information about datalink properties, you can use either of the following commands:

  • dladm show-linkprop –p property datalink

  • dladm show-ether datalink

Displaying Datalink Properties

To display a complete list of datalink properties, type the command without specifying a property, as shown in the following example:

$ dladm show-linkprop net1
net1     speed           r-   10000        10000        10000     -- 
net1     autopush        rw   --           --           --        -- 
net1     zone            rw   --           --           --        -- 
net1     duplex          r-   full         full         full      half,full 
more properties

Displaying Ethernet Property Values

Use the dladm show-ether –x command to obtain a range of information about Ethernet property values:

$ dladm show-ether -x net1
net1     current     up       yes   1G-f                     both
--       capable     --       yes   1G-fh,100M-fh,10M-fh     both
--       adv         --       yes   100M-fh,10M-fh           both
--       peeradv     --       yes   100M-f,10M-f             both

The –x option, displays more than default information and includes the built-in capabilities of the specified link, as well as the capabilities that are currently advertised between the host and the link partner.

    In the previous example, the following information is displayed:

  • For the Ethernet device's current state, the link is up and functioning at 1 Gigabits per second at full duplex. Its auto-negotiation capability is enabled and has bidirectional flow control, in which both the host and link partner can send and receive pause frames. This information is displayed in the first row of the output.

  • Subsequent rows of the output display information about datalink speed capabilities, actual datalink speeds that are advertised, as well as information from the peer system