Controlling the online state in Linux

Use the smc_rnics command or the sysfs power attribute of a PCI function to set it online or offline in Linux®.

Before you begin

Changing the online state of a PCI function from Linux in LPAR or DPM partition mode affects the configuration state of the PCI function in the partition, see Online and configuration state.

Procedure

Optional: List your PCI functions with the smc_rnics command to assure that the PCI function of interest is available to your partition. In the command, specify the -a option to include offline PCI functions in the command output.
The command displays a table of all PCI functions that are eligible for your partition. A 0 in the Power column of the output table indicates that the PCI function is offline.
Example: This example shows an offline PCI function with FID 0x050a.
```
# smc_rnics -a
  FID Power PCI_ID       PCHID Type          PPrt PNET_ID Net-Dev
-------------------------------------------------------------------
...
  50a 0
...
```
Set the PCI function online by issuing an smc_rnics command with the -e option or through sysfs.
- Issue a command of the following form:
```
# smc_rnics -e <fid>
```
  where <fid> specifies the FID in hexadecimal format. You can omit leading zeros.
  Hint: If the PCI function is already configured in another partition, you cannot set it online and the command fails.
  Example: To set a PCI function with FID 0x050a online, issue:
```
# smc_rnics -e 50a
```
- Alternatively, write 1 to the sysfs /sys/bus/pci/slots/<fid>/power attribute of the PCI function. In this path, <fid> is the function's FID as an 8-digit hexadecimal number.
  Example: To set a PCI function with FID 0x050a online, issue:
```
# echo 1 > /sys/bus/pci/slots/0000050a/power
```
The PCI function is now online to your Linux instance. The output table of the smc_rnics command now shows more information about the PCI function and 1 is displayed in the Power column.
Example:
```
# smc_rnics
  FID Power PCI_ID       PCHID Type          PPrt PNET_ID Net-Dev
-------------------------------------------------------------------
...
  50a 1     000a:00:00.0 015c  RoCE_Express  0    NET20   eno10
...
```

What to do next

You can now use the ip command to activate the interface that is provided by the PCI function. You can see the interface name in the Net-Dev column of your smc_rnics output table, eno10 in the example.

You can use the ethtool and ip commands for a transient configuration of your network interface. For a persistent configuration, use the network configuration tools of your distribution. For information about these tools, see your distributor's documentation.

To set a PCI function offline, use the smc_rnics command with the -d. Alternatively, write 0 to the sysfs power attribute of the PCI function.