Data Sheet

System Manageability—Ethernet Controller I210
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b. Check if a different channel is available (link is up).
c. If found:
• Enable network TX for that specific channel.
• Issue a gratuitous ARP (or any other packet with its source MAC address) to the network.
This packet informs the switch that this specific MAC address is registered to channel 0's
specific LAN port.
• Resume normal workflow.
• If not found, report the error and continue polling until a valid channel is found.
The above algorithm can be generalized such that the start-up and normal workflow are the same. In
addition, the BMC might need to use a specific channel (such as channel 0). In this case, the BMC
should switch the network transmit to that specific channel as soon as that channel becomes valid (link
is up).
Recommendations:
• Wait for a link-down-tolerance timeout before a channel is considered invalid. For example, a link
re-negotiation might take a few seconds (normally 2 to 3 or might be up to 9). Thus, the link must
be re-established after a short time.
• Typically, this timeout is recommended to be three seconds.
• Even when enabling and using AENs, periodically poll the link status, as dropped AENs might not be
detected.
10.6.8.4 Statistics
The BMC might use the statistics commands as defined in NC-SI. These counters are meant mostly for
debug purposes and are not all supported.
The statistics are divided into three commands:
1. Controller statistics — These are statistics on the network interface (to the Host operating system
and pass through traffic). See the NC-SI specification for details.
2. NC-SI statistics — These are statistics on the NC-SI control frames (such as commands, responses,
AENs, etc.). See the NC-SI specification for details.
3. NC-SI pass-through statistics — These are statistics on the NC-SI pass-through frames. See the
NC-SI specification for details.
10.6.9 External Link Control
The MC can use the NC-SI Set Link command to control the external interface link settings. This
command enables the MC to set the auto-negotiation, link speed, duplex, and other parameters.
This command is only available when the Host operating system is not present. Indicating the Host
operating system status can be obtained via the Get Link Status command and/or Host OS Status
Change AEN command.
Recommendation:
• Unless explicitly needed, it is not recommended to use this feature. The NC-SI Set Link command
does not expose all the possible link settings and/or features. This might cause issues under
different scenarios. Even if you decided to use this feature, use it only if the link is down (trust the
I210 until proven otherwise).