The Fibre Channel (FC) Transmission Control Protocol/Internet Protocol (TCP/IP) interface is configured in a manner similar to the configuration of other TCP/IP interfaces (for example, those used by Ethernet and Token-Ring adapters). Both the System Management Interface Tool (SMIT) and traditional ifconfig command methods are supported.
The configuration of the FC TCP/IP interface depends on the successful configuration of the FC device. The FC TCP/IP interface name is fc , followed by a number associated with the device (for example, fc0 ). The valid maximum transmission unit (MTU) values for the FC TCP/IP interface are 17 through 65532.
The Fibre Channel (FC) network does not have broadcast support; therefore, the internet control message protocol (ICMP) address resolution protocol (ARP) support must be set up differently than on traditional TCP/IP networks. There are two ways to configure ARP on a Fibre Channel network: set up the ARP entries manually, or set up an FC adapter to serve as an ARP server.
If an FC adapter is not available to use as an ARP server for the FC network, then it is necessary to manually enter all of the ARP entries. Issue the following command for each node on the network, besides the local node:
arp -s fcs ip_address nport_address
Note: The nport_address must be specified in hexadecimal format for the arp command.
If an FC adapter is available for use as an ARP server, then change the attribute ARP Server Support on the FC Adapter Driver (fcsdd) to true. This will allow support of dynamic ARP requests.
If the FC adapters are connected in a point-to-point configuration, it is not necessary to do any ARP configuration setup. It is automatically configured in a point-to-point connection.
To increase the performance of the Fibre Channel (FC) over TCP/IP, configure TCP/IP to take advantage of the High-Speed TCP/IP Extension (RFC 1323.) Configuring TCP/IP with RFC 1323 increases the maximum window size to 64KB and also increases a number of other important network options. The following example represents a script that can be used to set all of the appropriate network options to fully utilize the advantages of RFC 1323:
#!/bin/ksh
#
# Script to enable the High-Speed TCP/IP Extension (RFC 1323)
#
/etc/no -o sb_max=6000000 -o rfc1323=1 -o thewall=6000 \
-o lowclust=200 -o mb_cl_hiwat=2000
/etc/no -o tcp_sendspace=655360
/etc/no -o tcp_revcspace=655360
/etc/no -o udp_sendspace=655360
/etc/no -o udp_revcspace=655360
RFC 1323 must be configured on all nodes of the Fibre Channel network to ensure that the network fully utilizes the performance enhancements of the High-Speed TCP/IP Extension.
The default value (65280) of the MTU for an FC network assumes that the High-Speed TCP/IP Extension (RFC 1323) is configured on all nodes of the network. If RFC 1323 is not going to be configured on all nodes of the network, then the MTU size should be changed to 16384 to achieve the optimum performance of a network without RFC 1323 configured.
The MTU values mentioned in the previous paragraph were found to achieve the best network performance under most network conditions. It may be necessary to tune this value to best optimize the network to meet your requirements. To change the MTU size, issue the following command:
chdev -a "mtu=mtu_size" -l interface_name
| mtu_size | New MTU size (a decimal value). |
| interface_name | Name of the network interface to change (for example, fc0 ). |
After successful installation of the FC device driver, SMIT menus can be used to change FC device characteristics (attributes) and to perform other actions relating to the adapter, network services, and user applications.
To access FC-related menus, enter the following at the command line: