Virtual Device Identifier and Network Interface Name

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When you add a virtual switch or virtual network device to a domain, you can specify its device number by setting the id property.

primary# ldm add-vsw [id=switch-id] vswitch-name domain-name
primary# ldm add-vnet [id=network-id] if-name vswitch-name domain-name

Each virtual switch and virtual network device of a domain has a unique device number that is assigned when the domain is bound. If a virtual switch or virtual network device was added with an explicit device number (by setting the id property), the specified device number is used. Otherwise, the system automatically assigns the lowest device number available. In that case, the device number assigned depends on how virtual switch or virtual network devices were added to the system. The device number eventually assigned to a virtual switch or virtual network device is visible in the output of the ldm list-bindings command when a domain is bound.

The following example shows that the primary domain has one virtual switch, primary-vsw0. This virtual switch has a device number of 0 (switch@0).

primary# ldm list-bindings primary
...
VSW
    NAME         MAC               NET-DEV DEVICE   DEFAULT-VLAN-ID PVID VID MTU MODE
    primary-vsw0 00:14:4f:fb:54:f2 net0    switch@0 1               1    5,6 1500
...

The following example shows that the ldg1 domain has two virtual network devices: vnet and vnet1. The vnet device has a device number of 0 (network@0) and the vnet1 device has a device number of 1 (network@1).

primary# ldm list-bindings ldg1
...
NETWORK
    NAME  SERVICE              DEVICE    MAC               MODE   PVID VID MTU
    vnet  primary-vsw0@primary network@0 00:14:4f:fb:e0:4b hybrid 1        1500
    ...
    vnet1 primary-vsw0@primary network@1 00:14:4f:f8:e1:ea        1        1500
...

Similarly, when a domain with a virtual network device is running the Oracle Solaris OS, the virtual network device has a network interface, vnetN. However, the network interface number of the virtual network device, N, is not necessarily the same as the device number of the virtual network device, n.

Note - On Oracle Solaris 11 systems, generic link names in the form of netn are assigned to both vswn and vnetn. Use the dladm show-phys command to identify which netn names map to the vswn and vnetn devices.

Caution - The Oracle Solaris OS preserves the mapping between the name of a network interface and a virtual switch or a virtual network device based on the device number. If a device number is not explicitly assigned to a virtual switch or virtual network device, its device number can change when the domain is unbound and is later bound again. In that case, the network interface name assigned by the OS running in the domain can also change and make the existing system configuration unusable. This situation might happen, for example, when a virtual switch or a virtual network interface is removed from the configuration of the domain.

You cannot use the ldm list-* commands to directly determine the Oracle Solaris OS network interface name that corresponds to a virtual switch or virtual network device. However, you can obtain this information by using a combination of the output from ldm list -l command and from the entries under /devices on the Oracle Solaris OS.

Finding the Oracle Solaris 11 Network Interface Name

On Oracle Solaris 11 systems, you can use the ldm list-netdev command to find the Oracle Solaris OS network interface names. For more information, see the ldm(1M) man page.

The following example shows the ldm list-netdev and ldm list -o network commands. The ldm list -o network command shows the virtual network devices in the NAME field. The ldm list-netdev output shows the corresponding OS interface name in the NAME column.

primary# ldm list -o network ldg1
....
NETWORK
    NAME        SERVICE              ID DEVICE    MAC               MODE
    PVID VID MTU   MAXBW LINKPROP
    vnet0-ldg1  primary-vsw0@primary 0  network@0 00:14:4f:fa:eb:4e 1
             1500
    vnet1-ldg1  svcdom-vsw0@svcdom   1  network@1 00:14:4f:f8:53:45 4
             1500
           PVLAN :400,community

primary# ldm list-netdev ldg1
DOMAIN
ldg1

NAME CLASS MEDIA STATE   SPEED OVER  LOC
---- ----- ----- -----   ----- ----  ---
net0 VNET  ETHER up      0     vnet0 primary-vsw0/vnet0-ldg1
net1 VNET  ETHER up      0     vnet1 svcdom-vsw0/vnet1-ldg1
net2 VNET  ETHER unknown 0     vnet2 svcdom-vsw1/vnet2-ldg1

To verify that the ldm list-netdev output is correct, run the dladm show-phys and dladm show-linkprop -p mac-address commands from the ldg1:

ldg1# dladm show-phys
LINK     MEDIA     STATE      SPEED  DUPLEX         DEVICE
net0     Ethernet  up         0      unknown        vnet0
net1     Ethernet  up         0      unknown        vnet1
net2     Ethernet  unknown    0      unknown        vnet2

ldg1# dladm show-linkprop -p mac-address
LINK PROPERTY    PERM VALUE            EFFECTIVE        DEFAULT          POSSIBLE
net0 mac-address rw   0:14:4f:fa:eb:4e 0:14:4f:fa:eb:4e 0:14:4f:fa:eb:4e --
net1 mac-address rw   0:14:4f:f8:53:45 0:14:4f:f8:53:45 0:14:4f:f8:53:45 --

How to Find the Oracle Solaris OS Network Interface Name

This procedure describes how to find the Oracle Solaris OS network interface name in ldg1 that corresponds to net-c. This example also shows differences if you are looking for the network interface name of a virtual switch instead of a virtual network device. In this example procedure, guest domain ldg1 contains two virtual network devices, net-a and net-c.

Use the ldm command to find the virtual network device number for net-c.

primary# ldm list -l ldg1
...
NETWORK
NAME         SERVICE                     DEVICE       MAC
net-a        primary-vsw0@primary        network@0    00:14:4f:f8:91:4f
net-c        primary-vsw0@primary        network@2    00:14:4f:f8:dd:68
...

The virtual network device number for net-c is 2 (network@2).

To determine the network interface name of a virtual switch, find the virtual switch device number, n, as switch@n.

Find the corresponding network interface on ldg1 by logging into ldg1 and finding the entry for this device number under /devices.
```
ldg1# uname -n
ldg1
ldg1# find /devices/virtual-devices@100 -type c -name network@2\*
/devices/virtual-devices@100/channel-devices@200/network@2:vnet1
```
The network interface name is the part of the entry after the colon; that is, vnet1.

To determine the network interface name of a virtual switch, replace the argument to the –name option with virtual-network-switch@n\*. Then, find the network interface with the name vswN.

Verify that vnet1 has the MAC address 00:14:4f:f8:dd:68 as shown in the ldm list -l output for net-c in Step 1.

Oracle Solaris 11 OS.

Determine the name of the interface to specify for vnet1.

ldg1# dladm show-phys |grep vnet1
net2      Ethernet      up      0      unknown   vnet1

Determine the MAC address of net2.

# dladm show-linkprop -p mac-address net2
LINK PROPERTY    PERM VALUE             EFFECTIVE         DEFAULT POSSIBLE
net2 mac-address rw   00:14:4f:f8:dd:68 00:14:4f:f8:dd:68 --      --

This example MAC address matches the output of the ldm list -l command for net-c in Step 1.

Oracle Solaris 10 OS.

ldg1# ifconfig vnet1
vnet1: flags=1000842<BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 3
          inet 0.0.0.0 netmask 0
          ether 0:14:4f:f8:dd:68