Using Priority-Based Flow Control Capable Ethernet Adapters

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Traditional Ethernet adapters support only the IEEE 802.3x PAUSE function. The priority-based flow control (PFC) capable Ethernet adapters require a card which supports the IEEE 802.1Qbb/802.3bd standard. For example, if you are using a 10G Ethernet, you must use the Intel 10G Ethernet adapter.

With the configuration of a PFC capable Ethernet adapter connected to the CEE enabled DCBX FCoE switch, you can transfer iSCSI signals between the peers.

You can use the following hardware components to deploy FCoE on Oracle Solaris:

CEE-DCBX FCoE switch
PFC capable Ethernet adapter

The following figure shows the connection with CEE-DCBX FCoE switch by using a PFC capable Ethernet adapter.

Figure 2 Connection With CEE-DCBX FCoE Switch by Using a PFC Capable Ethernet Adapter

image:Connecting to CEE-DCBX FCoE Switch by Using PFC Capable Ethernet Adapter

How to Connect to CEE-DCBX FCoE Switch by Using Priority-Based Flow Control

Enable PFC on the NIC and set the MTU as required.
In the following example, the NIC MTU is set to 2500 to accommodate the FCoE payload.
```
# dladm set-linkprop -p mtu=2500 net10
```
Set priority-based Flow Control (PFC).
1. Set the dcb_mode to 1 in the NIC driver file /etc/driver/drv/ixgbe.conf.
```
dcb_mode=1;
```
2. Run the update_drv ixgbe or reboot command.
```
# update_drv ixgbe
```
  Or
```
# reboot
```
Tip - If the update_drv command fails to unload the ixgbe module, reboot the Oracle Solaris system.
Set the NIC flow control to auto or pfc.
auto – Transfers IEEE packets by default. However, when the host receives CEE packets from the peer, the mode switches to CEE automatically.
- To set the flow control to auto:
```
# dladm set-linkprop -p flowctrl=auto net10
```
- To set the flow control to pfc:
```
# dladm set-linkprop -p flowctrl=pfc net10
```
Note - The Oracle Solaris FCoE software framework supports only the ixgbe driver. The LLDP and FCoE software stack does not work without enabling PFC.

Check the effective value of the NIC settings.

# dladm show-linkprop -p mtu,flowctrl,ntcs net10
LINK     PROPERTY        PERM VALUE        EFFECTIVE    DEFAULT   POSSIBLE
net10    mtu             rw   2500         2500         1500      576-15500
net10    flowctrl        rw   auto         pfc          no        no,tx,rx,bi,
                                                                  pfc,auto
net10    ntcs            r-   8            8            0         --