Deployment Guide

Network Connections control panel. The description under the NIC name or in the Adapter Properties is

displayed as Chelsio Network Adapter.

Figure 23. Viewing the Chelsio network adapter

Configuring the firewall for the Chelsio adapters

Chelsio adapters use iWARP RDMA technology that use TCP/IP for communications. To facilitate TCP/IP

communications, add a firewall rule to the SMB server to allow incoming network traffic from the server

message block (SMB) Direct clients. In Windows Server 2012 R2, SMB Direct with iWARP uses TCP port

5445 and the traditional 445 port used for SMB.

1. Start a Windows PowerShell instance with Administrative privileges.

2. To enable the incoming firewall rule to allow access by the client servers at the CLI, enter the

following command.

Enable-NetFirewallRule FPSSMBD-iWARP-In-TCP

The FPSSMBD-iWARP-In-TCP command allows incoming network traffic on port 5445.

Jumbo frames for Chelsio adapter

Ensure that the MTU size is set to 9 KB on the Chelsio adapter. Also, ensure that the flow control is

enabled.

Enabling SMB Direct

An advantage of iWARP RDMA technology is that you can route it across different subnets. While the

common setup is a single subnet, the Chelsio RDMA adapter can connect servers across subnets; but this

capability is disabled by default on Windows Server 2012 R2.

To enable SMB Direct for operation with a Chelsio adapter, you must configure every server (SMB Servers

and SMB Clients) to allow routing RDMA across subnets. SMB client configuration is not described in this

document and you must configure it separately.

1. Start a Windows PowerShell instance with Administrative privileges.

2. Run the following PowerShell cmdlet to enable SMB routing.

Set-NetOffloadGlobalSetting -NetworkDirectAcrossIPSubnets Allowed

3. Disabling and reenabling the interface makes the settings change effective without a restart. Run the

following commands at the PowerShell prompt, where <string> is the name of the NIC (External1,

External2).

Disable-NetAdapter -InterfaceAlias <string>

Enable-NetAdapter -InterfaceAlias <string>