About logical interconnect groups

One or more logical interconnect groups are associated with an enclosure group and are used to define the logical interconnect configuration for every enclosure that is using that enclosure group. Logical interconnect group configurations include the I/O bay occupancy, uplink sets, available networks based on the uplink sets and internal networks, and downlinks.

All references to a logical interconnect group by an enclosure group or logical interconnect must be removed before you can delete the logical interconnect group.

About multiple logical interconnect groups in an enclosure group

Multiple logical interconnect groups can be associated with one enclosure group.

The advantages of using multiple logical interconnect groups in an enclosure group are:

  • Having air-gap separation between Ethernet networks to allow isolation of network traffic

  • Eliminating the need for stacking cables between interconnects, freeing uplink ports for data center traffic

  • Doubling the number of networks in an active/active configuration. See About active/active and active/standby configurations for more information.

Logical interconnect group requirements

  • Interconnects in horizontally adjacent bays must contain the same interconnect type or an empty bay

When to create a logical interconnect group

By default, a single logical interconnect group containing all the interconnects in the enclosure is automatically created when you add an enclosure, unless you create the logical interconnect group(s) before adding the enclosure. If you want to have multiple logical interconnects in an enclosure:

About copying a logical interconnect group

To streamline the creation of logical interconnect groups, you can copy existing logical interconnect groups.

When you copy a logical interconnect group, all the settings, uplink sets, and networks copy to the new group. The new group is not associated automatically with enclosure groups or logical interconnects. After copying a logical interconnect group, you can edit the logical interconnect group or associate it to an enclosure group.

For example, you have an existing logical interconnect group and you want a new group with the same settings, except a different internal network. Copy the existing logical interconnect group, and then edit the new logical interconnect group to change the internal network.

More information

“Copy a logical interconnect group” in the online help

About uplink sets in a logical interconnect group

The uplink sets portion of the logical interconnect group defines the initial configuration for uplink sets for each logical interconnect in the enclosure group. If you change the uplink sets for an existing logical interconnect group, only enclosures that you add after the configuration change are configured with the new uplink set configuration. Changing uplink sets in a logical interconnect group makes the logical enclosure and logical interconnects associated with it inconsistent with the logical interconnect group. Select Update from group to bring the logical enclosure and logical interconnect back into compliance with the changes made to the logical interconnect group.

About Link Layer Discovery Protocol (LLDP) tagging

Link Layer Discovery Protocol (LLDP) information is sent by devices at a fixed interval in the form of an Ethernet frame. Each frame contains one LLDP Data Unit (LLDPDU). Each LLDPDU is a sequence of type-length-value (TLV) structures.

Untagged LLDP frames

By default, Virtual Connect interconnects use untagged LLDP frames to advertise their identity and learn about their link partners. LLDP advertises the Virtual Connect interconnect’s management IP addresses to uplink, downlink, and stacking link ports. LLDP frames also identify stacking links in a logical interconnect.

The IPv4 address (and IPv6 address if enabled) are used as the LLDP management address TLV.

Tagged LLDP frames

LLDP can also be used to communicate with a virtual switch in the hypervisor through the use of tagged LLDP frames on downlink ports. The tagged frame contains the VLAN ID that identifies the subport of the configured FlexNIC. This information is used to build the network topology.

LLDP tagging can be enabled or disabled through the HPE OneView UI or REST API.

More information

Enable or disable LLDP tagging using REST APIs
About logical interconnect groups
About logical interconnects

About enhanced type-length-value (TLV) structure

Enhanced TLV is part of the Link Layer Discovery Protocol (LLDP) exchange of information between interconnects. Enhanced TLV determines what is contained on the Chassis ID TLV of LLDP frames sent out by an interconnect.

Enhanced TLV can be enabled or disabled through the HPE OneView UI or REST API.

Enable

The Chassis ID TLV advertises the enclosure name and serial number to other interconnects

Disable

The Chassis ID TLV contains the switch MAC address

Enhanced TLV values

Enable enhanced TLV format

  • System name (<hostname><serial number>BAY:<bay_number>)

  • Chassis ID (ENC:<enclosure_name>:SERIAL NO:<enclosure_serial_number>

  • Part description (<op_speed>/<connector_type>)

Disable enhanced TLV format
  • System name (<hostname>)

  • Chassis ID (<switch_mac_address>)

  • Part description (IF-MIB::ifDescr value), for example HPE VC FlexFabric 10Gb/24–Port Module 4.10 X1

More information

Enable or disable enhanced TLV support using REST APIs
About logical interconnect groups
About logical interconnects