IBM Brocade, Инструкция по установке и эксплуатации

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Introduction 11
Features, specifications, and standards
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Ethernet flow control
Ethernet flow control is a mechanism for managing data transmission between two network
nodes to prevent a fast sender from over running a slow receiver. When an overwhelmed
receiver generates a PAUSE frame, this halts transmission for a specified period of time.Traffic
resumes when time specified in the frame expires or PAUSE zero is received.
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Flexible MAC address
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Header data split (HDS) feature for advanced link layer
Enables Network Driver Interface Specification (NDIS) miniport to split incoming packets into
header and data payload, which are mapped to two or more memory descriptor lists. Increases
system performance through intelligent cache management.
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Intermediate driver
This provides support for teaming and for multiple VLANs on Windows systems. You can install
this driver with other adapter software.
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Link aggregation (NIC teaming)
A network interface “team” is a collection of physical Ethernet interfaces (adapter ports) acting
a single interface. Teaming overcomes problems with bandwidth limitation and redundancy
often associated with Ethernet connections. Combining (aggregating) ports can increase the
link speed beyond the limits of one port and provide redundancy. You can team up to eight
ports across multiple adapters in three modes: failover, failback, or 802.3ad.
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Failover mode provides fault tolerance. Only one port in a team is active at a time (primary
port), and the others are in standby mode. If the primary port goes down, a secondary port
is chosen using a round-robin algorithm as the next primary. This port continues to be
primary, even if the original primary port returns.
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Failback mode is an extension of the Failover mode. In addition to the events that occur
during a normal failover, if the original primary port comes back up, that port again
becomes the primary port.
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802.3ad is an IEEE specification that includes Link Aggregation Control Protocol (LACP) as
a method to control how several physical ports bundle to form a single logical channel.
LACP allows a network device to negotiate automatic bundling of links by sending LACP
packets to the peer (a device directly connected to a device that also implements LACP).
This mode provides larger bandwidth in fault tolerance.
Configuration is required on the switch for NIC teaming to function.
Be aware when configuring ports for teaming that converged FCoE and network traffic is not
supported on ports that participate in an IEEE 802.3ad-based team. This must be enforced by
the user as there is no mechanism to control this in the software.
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Interrupt coalescing
To avoid flooding the host system with too many interrupts, this allows the system to reduce the
number of interrupts generated by generating a single interrupt for multiple packets.
Increasing the “coalescing timer” should lower the interrupt count and lessen CPU utilization.