82598EB Datasheet, PDF (420/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - Pass-Through Multi-Port Modes
• MAC address filters
Each of these are discussed in detail later in this section.
5.3.3 Pass-Through Multi-Port Modes
Pass-through configuration depends on the way the LAN ports are configured. If the LAN ports are
configured as two different channels (non-teaming mode), then 82598EB is presented on the
manageability link as two different devices. For example, via two different SMB addresses on which
each device is connected to a different LAN port. In this mode (the same as in the LAN channels), there
is no logical connection between the two devices. In this mode the fail-over between the two LAN ports
is done by the external BMC (by sending/receiving packets through different devices). The status report
to the BMC, ARP handling, DHCP, and other pass-through functionality are unique for each port.
When the LAN ports are configured to work as one LAN channel (teaming mode), 82598EB presents
itself on the SMBus as one device (one SMB address). In this mode, the external BMC is not aware that
there are two LAN ports. The 82598 decides how to route the packet that it receives from the LAN
according to the fail-over algorithm. The status report to the BMC and other pass-through configuration
are common to both ports.
5.3.3.1 Automatic Ethernet ARP Operation
Automatic Ethernet ARP parameters are loaded from the EEPROM when the 82598 is powered up or
configured through the sideband management interface. The following parameters should be configured
in order to enable ARP operation:
• ARP auto-reply enabled
• ARP IP address (to filter ARP packets)
• ARP MAC addresses (for ARP responses)
These are all configurable over the sideband interface using the advanced version of the Receive Enable
command (see Section 5.3.10.1.3) or using the EEPROM.
When an ARP request packet is received on the wire, and ARP auto-reply is enabled, the 82598 checks
the targeted IP address (after the packet has passed L2 checks and ARP checks). If the targeted IP
matches the IP 82598EB was configured to, than it replies with an ARP response. The 82598 responds
to ARP request targeted to the ARP IP address with the ARP MAC address configured to it. In case that
there is no match, the 82598 silently discards the packets. If 82598EB is not configured to do auto-ARP
response it forwards the ARP packets to the BMC.
When the external BMC uses the same IP and MAC address of the OS, the ARP operation should be
coordinated with the OS operation. In this mode, this is the external BMC’s responsibility and 82598EB
stops/starts doing automatic ARP response as configured.
5.3.3.2 Manageability Receive Filtering
This section describes the manageability receive packet filtering flow when in SMBus mode. The
description applies to a capability of each of 82598EB LAN ports. Packets that are received by 82598EB
can be discarded, sent to the host memory, sent to the external BMC, or sent to both BMC and host
memory.
5.3.3.2.1 Overview and General Structure
There are two modes of receive manageability filtering:
1. Receive Filtering - In this mode only certain types of packets are directed to the manageability
block. The BMC should set the RCV_TCO_EN bit together with the specific packet type bits in the
manageability filtering registers.
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