HP Virtual Connect Flex-10/10D Module Enterprise Edition for BLc7000 HP Virtua - Page 93

o Set maximum connection speed. This value is the maximum speed for server profile connections mapped to this network. 2. Click Apply. Virtual Connect can only control link speed for Flex-10 NICs when they are connected to an HP Virtual Connect Flex-10 Module. Virtual Connect cannot control the link speed of traditional NICs. For more information, see "Flex-10 overview (on page 138)." IMPORTANT: Each FlexNIC and FlexHBA is recognized by the server as a PCIe physical function device with adjustable speeds from 100Mb to 10Gb in 100Mb increments when connected to an NC553i/m 10Gb 2-port FlexFabric Converged Network Adapter or any Flex-10 NIC. For NC551i/m Dual Port FlexFabric 10Gb Converged Network Adapters, the range is limited to 1Gb to 10Gb in 100Mb increments. MAC Cache Failover When a VC-Enet uplink that was previously in standby mode becomes active, external Ethernet switches can take several minutes to recognize that the c-Class server blades can now be reached on this newly active connection. Enabling Fast MAC Cache Failover causes Virtual Connect to transmit Ethernet packets on newly active links, which enables the external Ethernet switches to identify the new connection and update their MAC caches appropriately. This transmission sequence repeats a few times at the MAC refresh interval (HP recommends 5 seconds) and completes in about 1 minute. Virtual Connect only transmits MAC Cache update frames on VLANs that have been configured in the VC domain. The update frames are VLAN tagged appropriately for networks defined on shared uplink sets. For dedicated networks, only untagged update frames are generated, regardless of whether or not VLAN Tunneling is enabled. In a VLAN tunnel, all customer VLAN tags pass through Virtual Connect transparently. Virtual Connect does not examine nor record VLAN tag information in tunneled networks; therefore, it cannot generate tagged update frames. IMPORTANT: Be sure to set switches to allow MAC addresses to move from one port to another without waiting for an expiration period or causing a lock out. Always enable the "spanning tree portfast" feature to allow the switch port to bypass the "listening" and "learning" stages of spanning tree and quickly transition to the "forwarding" stage, allowing edge devices to immediately begin communication on the network. IGMP Snooping The IGMP Snooping feature enables VC-Enet modules to monitor (snoop) the IGMP IP multicast membership activities and configure hardware Layer 2 switching behavior of multicast traffic to optimize network resource usage. IGMP v1, v2, and v3 snooping are supported. The IGMP Snooping idle timeout interval is set to 260 seconds by default. This value is the "Group Membership Interval" value as specified by IGMP v2 specification (RFC2236). For optimum network resource usage, set the interval to match the configuration on the customer network's multicast router settings. By default, unregistered IGMP multicast traffic traversing VC-Enet modules is flooded on the configured Ethernet network. To prevent flooding, select the Prevent flooding of unregistered multicast traffic option. Unregistered multicast traffic from uplinks is dropped and traffic from the server ports is redirected to the active uplink port. IGMP Snooping must be enabled to modify this setting. Virtual Connect networks 93