HPE FlexFabric Switches DRNI Configuration Guide

Document version: 6W100-20231114

HPE FlexFabric Switches

DRNI Configuration Guide

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1

Contents

DRNI network planning ·················································································· 1

Comparison between IRF and DRNI ················································································································· 1

Overlay network planning··································································································································· 2

Underlay network planning································································································································· 5

Restrictions and guidelines for DR system setup······························································································· 7

Restrictions and guidelines ································································································································ 9

DRNI network models ·················································································· 13

Layer 2 DRNI network models ························································································································· 13

Loop prevention on a DR system ············································································································· 13

DRNI and spanning tree ··························································································································· 13

DRNI and VSI-based loop detection ········································································································ 15

Layer 3 DRNI network models ························································································································· 17

Gateway deployment schemes ················································································································ 17

Dual-active VLAN interfaces ···················································································································· 17

Routing neighbor relationship setup on dual-active VLAN interfaces using DRNI virtual IP addresses ·· 22

VRRP gateways ······································································································································· 23

Restrictions and guidelines for single-homed servers attached to non-DR interfaces ····························· 25

Restrictions and guidelines for routing configuration ··············································································· 26

DRNI and RDMA ·············································································································································· 26

Network model ········································································································································· 26

Restrictions and guidelines ······················································································································ 28

DRNI and EVPN··············································································································································· 28

Distributed gateway deployment ·············································································································· 29

Centralized gateway deployment ············································································································· 30

Failover between data centers ················································································································· 31

Basic configuration restrictions and guidelines ························································································ 31

Restrictions and guidelines for IPL ACs ··································································································· 33

MAC address configuration restrictions and guidelines ··········································································· 33

Leaf device configuration restrictions and guidelines ··············································································· 34

Border and ED configuration restrictions and guidelines ········································································· 34

Restrictions and guidelines for server access in active/standby mode ···················································· 34

Routing neighbor relationship setup on a DR system formed by distributed EVPN gateways ························ 34

DRNI, EVPN, and DHCP relay ························································································································ 35

About this deployment scheme ················································································································ 35

Restrictions and guidelines ······················································································································ 37

EVPN distributed relay, microsegmentation, and service chain······································································· 37

Network model ········································································································································· 37

DRNI and underlay multicast ··························································································································· 39

DRNI and MVXLAN·········································································································································· 39

DRNI and DCI ·················································································································································· 41

Management network design ··························································································································· 42

High availability for DRNI ············································································· 44

High availability of uplinks ································································································································ 44

High availability of leaf devices ························································································································ 44

High availability of border devices···················································································································· 47

Recommended hardware and software versions ········································· 50

1

DRNI network planning

Comparison between IRF and DRNI

The Intelligent Resilient Framework (IRF) technology is developed by HPE to virtualize multiple

physical devices at the same layer into one virtual fabric to provide data center class availability and

scalability. IRF virtualization technology offers processing power, interaction, unified management,

and uninterrupted maintenance of multiple devices.

Distributed Resilient Network Interconnect (DRNI) virtualizes two physical devices into one system

through multi-chassis link aggregation for device redundancy and traffic load sharing.

Table 1 shows the differences between IRF and DRNI. For high availability and short service

interruption during software upgrade, use DRNI. You cannot use IRF and DRNI in conjunction on

the same device.

Table 1 Comparison between IRF and DRNI

Item

IRF

DRNI

Control plane

• The IRF member devices have a

unified control plane for central

management.

•

The IRF member devices

synchronize all forwarding

entries.

• The control plane of the DR member

devices is separate.

• The DR member devices synchronize

entries such as MAC, ARP, and ND entries.

Device

requirements

• Hardware: The chips of the IRF

member devices must have the

same architecture, and typically

the IRF member devices are from

the same series.

•

Software: The IRF member

devices must run the same

software version.

• Hardware: The DR member devices can be

different models.

•

Software: Some device models can run

different software versions when they act as

DR member devices.

Full support for

differe

nt software versions will be

implemented in the future.

Software

upgrade

•

The IRF member devices are

upgraded simultaneously or

separately. A separate upgrade is

complex.

•

Services are interrupted for 30

seconds or longer during a

device-by-device upgrade without

ISSU. Services are interrupted for

about 2 seconds during an ISSU

upgrade.

The DR member

devices are upgrade

separately, and the service interruption time is

shorter than 1 second during an upgrade.

If the software supports

graceful insertion and

removal (GIR), an upgrade does not interrupt

services.

Management

The IRF member devices are

configured and managed in a unified

manner.

S

ingle points of failure might occur

when a controller manages the IRF

member devices.

The DR member

devices are configured

separately, and they can perform configuration

consistency check for you to remove

inconsistencies in the configuration

that affects

operation of the DR system.

You must ensure

that service features also have consistent

configuration.

The DR member

devices are managed

separately. No single point of failure will occur

when a controller manages the DR member

devices.

2

NOTE:

GIR enables you to gracefully isolate

a

device from the network for device maintenance or upgrade.

GIR minimize

s service interruption by instructing the affected protocols (for example, routing

protocols) to isolate the device and switch over to the redundant path. You do not need to configure

graceful switchover protocol by protocol.

For more information about GIR, see Fundamentals

Configuration Guide for the devices.

Overlay network planning

HPE offers the following overlay network models for DRNI:

•

Three-tiered overlay—The overlay network is formed by the leaf, spine, and border tiers, as

shown in Figure 1. Use this model if the border devices do not have enough downlink

interfaces to connect to all leaf devices. The spine devices act as route reflectors (RR) in the

network.

•

Two-tiered overlay—The overlay network is formed by the leaf and spine tiers, and the spine

devices are also border devices, as shown in Figure 2.

3

Figure 1 Three-tiered overlay network model

Virtualization

server Bare metal

server

IPL

Leaf 1

Virtualization

server Bare metal

server

Leaf 2

Spine 1

BGP RR Spine 2

BGP RR

Border

devices/EDs IPL

FW

ECMP

LB

IPL

Keepalive Keepalive

Keepalive

Border devices/EDs in

a remote DC

IPL

Keepalive

Internet

PE/Core 1PE/Core 2

ECMP

4

Figure 2 Two-tiered overlay network model

The overlay network contains the following device roles:

•

Border device—A border gateway with DRNI configured. The border devices are attached to

firewalls and load balancers by using DR interfaces. The border devices use Layer 3 Ethernet

interfaces to connect to the spine or leaf devices, and traffic is load shared among the Layer 3

Ethernet links based on ECMP routes.

On a border device, you can use a Layer 3 Ethernet interface, VLAN interface, or DR interface

to establish Layer 3 connections with a PE or core device. As a best practice, use Layer 3

Ethernet interfaces.

•

Edge device (ED)—A device providing Layer 2 and Layer 3 connectivity to another data

center by using VXLAN. You can deploy independent EDs, configure EDs to be collocated with

border devices, or configure a device to act as an ED, border, and spine device.

•

Spine device—An RR does not have DRNI configuration and reflects BGP routes between

the border and leaf tiers in the three-tiered network model. An RR performs only underlay

forwarding, and ECMP routes are used for traffic load sharing among the spine, border, and

leaf tiers.

In a small network, spine devices can be collocated with border devices.

•

Leaf device—A DRNI-configured gateway for the servers. If the server NICs operate in bond4

mode for load sharing, a leaf device is connected to the servers by using DR interfaces. If the

server NICs operate in bond1 mode for link backup, a leaf device is connected to the servers

Virtualization

server Bare metal

server

IPL

Leaf 1

Virtualization

server Bare metal

server

Leaf 2

Border/Spine

devices

IPL

FW

LB

IPL

Keepalive Keepalive

Keepalive

EDs

IPL

Keepalive

Internet

PE/Core 1 PE/Core 2

Remote DC

ECMP

5

by using physical interfaces assigned to the same VLAN as the servers. As a best practice to

reduce active/standby NIC switchovers upon link flapping, disable active link preemption or set

a preemption delay.

For high availability, make sure the servers are dualhomed to the leaf devices.

A leaf device is connected to upstream devices by using Layer 3 Ethernet interfaces, and

ECMP routes are configured for high availability and load sharing.

•

Firewall (FW)—An internal firewall attached to the DR interfaces on the border devices by

using two aggregate interfaces, one for the uplink and one for the downlink. Static routes are

configured to enable Layer 3 communication between the firewall and border devices.

•

Load balancer (LB)—A load balancer attached to the DR interfaces on the border devices by

using an aggregate interface. Static routes are configured to enable Layer 3 communication

between the load balancer and border devices.

Underlay network planning

HPE offers the following underlay network models:

•

DRNI at the spine and leaf tiers—If the network is large, set up DR systems at the spine and

leaf tiers, and configure the spine devices as gateways for the servers. For configuration

examples, see Multi-tier DRNI+Spine Gateways+ECMP Paths to External Network

Configuration Example.

•

DRNI at the leaf tier—If the network is small, set up DR systems at the leaf tier, and configure

the leaf devices as gateways for the servers. Configure ECMP routes between the leaf and

spine tiers.

6

Figure 3 DRNI at the spine and leaf tiers

Server Server

IPL

Leaf 1

Server Server

Leaf 2

Spine

(gateway)

IPL

Keepalive Keepalive

Keepalive

Internet

PE/Core 1 PE/Core 2

ECMP

7

Figure 4 DRNI at the leaf tier

Restrictions and guidelines for DR system setup

IPL

In addition to protocol packets, the IPL also transmits data packets between the DR member

devices when an uplink fails.

If a DR member device is a modular device, assign at least one port on each slot to the aggregation

group for the IPP as a best practice. This configuration prevents asynchronous service module

reboots from causing IPL flapping after a device reboot. As a best practice, make sure at least one

member port resides on a different slot than the uplink interfaces.

If a DR member device is a fixed-port device with interface expansion modules, assign ports from

multiple interface expansion modules to the aggregation group for the IPP. As a best practice, make

sure at least one member port resides on a different interface expansion module than the uplink

interfaces.

If a DR member device is a fixed-port device, assign at least two physical interfaces to the

aggregation group for the IPP.

Make sure the member ports in the aggregation group for the IPP have the same speed.

If a leaf-tier DR system is attached to a large number of servers whose NICs operate in

active/standby mode, take the size of the traffic sent among those servers into account when you

determine the bandwidth of the IPL.

Server Server

IPL

Leaf 1

(gateway)

Server Server

Leaf 2

(gateway)

Spine 1

IPL

Keepalive Keepalive

Internet

PE/Core 1 PE/Core 2

ECMP

Spine 2

8

As a best practice to reduce the impact of interface flapping on upper-layer services, use the

link-delay command to configure the same link delay settings on the IPPs. Do not set the link

delay to 0.

To prevent data synchronization failure, you must set the same maximum jumbo frame length on

the IPPs of the DR member devices by using the jumboframe enable command.

Keepalive link

The DR member devices exchange keepalive packets over the keepalive link to detect multi-active

collisions when the IPL is down.

As a best practice, establish a dedicated direct link between two DR member devices as a

keepalive link. Do not use the keepalive link for any other purposes. Make sure the DR member

devices have Layer 2 and Layer 3 connectivity to each other over the keepalive link.

You can use management Ethernet interfaces, Layer 3 Ethernet interfaces, Layer 3 aggregate

interfaces, or interfaces with a VPN instance bound to set up the keepalive link. As a best practice,

do not use VLAN interfaces for keepalive link setup. If you have to use VLAN interfaces, remove the

IPPs from the related VLANs to avoid loops.

If a device has multiple management Ethernet interfaces, you can select one from them to set up a

dedicated keepalive link independent of the management network.

On a modular device or fixed-port device with interface expansion modules, do not use the same

module to provide interfaces for setting up the keepalive link and IPL.

For correct keepalive detection, you must exclude the physical and logical interfaces used for

keepalive detection from the shutdown action by DRNI MAD.

DR interface

DR interfaces in the same DR group must use the different LACP system MAC addresses.

As a best practice, use the undo lacp period command to enable the long LACP timeout timer

(90 seconds) on a DR system.

You must execute the lacp edge-port command on the DR interfaces attached to bare metal

servers.

DRNI MAD

Follow these restrictions and guidelines when you exclude interfaces from the shutdown action by

DRNI MAD on the underlay network:

•

By default, DRNI MAD shuts down network interfaces after a DR system splits.

•

You must exclude the VLAN interfaces of the VLANs to which the DR interfaces and IPPs

belong.

•

For correct keepalive detection, you must exclude the interfaces used for keepalive detection.

•

Do not exclude the uplink Layer 3 interfaces, VLAN interfaces, or physical interfaces.

When you use EVPN in conjunction with DRNI, follow these restrictions and guidelines:

•

Set the default DRNI MAD action to NONE by using the drni mad default-action none

command.

•

Do not configure the DRNI MAD action on the VLAN interfaces of the VLANs to which the DR

interfaces and IPPs belong. These interfaces will not be shut down by DRNI MAD. Use the

drni mad include interface command to include the non-DR interfaces attached to

single-homed servers in the shutdown action by DRNI MAD. These interfaces will be shut

down by DRNI MAD when the DR system splits.

•

Do not configure the DRNI MAD action on aggregation member ports. These interfaces will be

shut down by DRNI MAD after a DR system splits.

•

If you use an Ethernet aggregate link as an IPL, add the uplink Layer 3 interfaces, VLAN

interfaces, and physical interfaces to the list of included interfaces by using the drni mad

9

include interface command. These interfaces will be shut down by DRNI MAD. This

restriction does not apply to a VXLAN tunnel IPL.

•

Do not configure the DRNI MAD action on the interfaces used by EVPN, including the VSI

interfaces, interfaces that provide BGP peer addresses, and interfaces used for setting up the

keepalive link. These interfaces will not be shut down by DRNI MAD.

•

Do not configure the DRNI MAD action on the interface that provides the IP address specified

by using the evpn drni group command. These interfaces will not be shut down by DRNI

MAD.

When you configure DRNI MAD, use either of the following methods:

•

To shut down all network interfaces on the secondary DR member device except a few

special-purpose interfaces that must be retained in up state:

 Set the default DRNI MAD action to DRNI MAD DOWN by using the drni mad

default-action down command.

 Exclude interfaces from being shut down by DRNI MAD by using the drni mad exclude

interface command.

In some scenarios, you must retain a large number of logical interfaces (for example, VSI

interfaces, VLAN interfaces, aggregate interfaces, tunnel interfaces, and loopback interfaces)

in up state. To simplify configuration, you can exclude all logical interfaces from the shutdown

action by DRNI MAD by using the drni mad exclude logical-interfaces command.

•

To have the secondary DR member device retain a large number of interfaces in up state and

shut down the remaining interfaces:

 Set the default DRNI MAD action to NONE by using the drni mad default-action

none command.

 Specify network interfaces that must be shut down by DRNI MAD by using the drni mad

include interface command.

If you configure inter-VPN static routes without a next hop in ADDC 6.2 or a later solution, you must

perform the following tasks for the static routes to take effect:

1. Create a service loopback group, and then assign an interface to it.

2. Access the DR system editing page and exclude that interface from the shutdown action by

DRNI MAD.

Restrictions and guidelines

DRNI compatibility with third-party devices

You cannot use DR interfaces for communicating with third-party devices.

DR system configuration

You can assign two member devices to a DR system. For the DR member devices to be identified

as one DR system, you must configure the same DR system MAC address and DR system priority

on them. You must assign different DR system numbers to the DR member devices.

Make sure each DR system uses a unique DR system MAC address.

To ensure correct forwarding, delete DRNI configuration from a DR member device if it leaves its

DR system.

When you bulk shut down physical interfaces on a DR member device for service changes or

hardware replacement, shut down the physical interfaces used for keepalive detection prior to the

physical member ports of the IPP. If you fail to do so, link flapping will occur on the member ports of

DR interfaces.

10

Do not execute the drni drcp period short command to enable the short DRCP timeout timer

when the DRNI process is restarting or before you perform an ISSU. If you do so, traffic forwarding

will be interrupted during the DRNI process restart or ISSU.

DRNI standalone mode

The DR member devices might both operate with the primary role to forward traffic if they have DR

interfaces in up state after the DR system splits. DRNI standalone mode helps avoid traffic

forwarding issues in this multi-active situation by allowing only the member ports in the DR

interfaces on one member device to forward traffic.

The following information describes the operating mechanism of this feature.

The DR member devices change to DRNI standalone mode when they detect that both the IPL and

the keepalive link are down. In addition, the secondary DR member device changes its role to

primary.

In DRNI standalone mode, the LACPDUs sent out of a DR interface by each DR member device

contain the interface-specific LACP system MAC address and LACP system priority.

The Selected state of the member ports in the DR interfaces in a DR group depends on their LACP

system MAC address and LACP system priority. If a DR interface has a lower LACP system priority

value or LACP system MAC address, the member ports in that DR interface become Selected to

forward traffic. If those Selected ports fail, the member ports in the DR interface on the other DR

member device become Selected to forward traffic.

To configure the DR system priority, use the drni system-priority command in system view.

To configure the LACP system priority, use one of the following methods:

•

Execute the lacp system-mac and lacp system-priority commands in system view.

•

Execute the port lacp system-mac and port lacp system-priority commands in DR

interface view.

The DR interface-specific configuration takes precedence over the global configuration.

When you configure the DR system priority and LACP system priority, follow these guidelines:

•

For a single tier of DR system at the leaf layer, set the DR system priority value to be larger

than the LACP system priority value for DR interfaces. The smaller the value, the higher the

priority. For a DR group, configure different LACP system priority values for the member DR

interfaces.

•

For two tiers of DR systems at the spine and leaf layers, configure the DR system priority

settings of spine devices to be the same as the LACP system priority settings of leaf devices.

This ensures traffic is forwarded along the correct path when a DR system splits.

IPP configuration

To ensure correct Layer 3 forwarding over the IPL, you must execute the undo mac-address

static source-check enable command to disable static source check on the Layer 2

aggregate interface assigned the IPP role. This restriction does not apply to the HPE FlexFabric

12900E switches.

DRNI data restoration interval

The data restoration interval set by using the drni restore-delay command specifies the

maximum amount of time for the secondary DR member device to synchronize forwarding entries

with the primary DR member device during DR system setup. Adjust the data restoration interval

based on the size of forwarding tables. If the DR member devices have small forwarding tables,

reduce this interval. If the forwarding tables are large, increase this interval. Typically, set the data

restoration interval to 300 seconds. If the ARP table of an HPE FlexFabric 12900E switch contains

about 48K entries, set this interval to 900 seconds.

IRF

The HPE FlexFabric 12900E Switch Series (Type K) do not support IRF.

11

DRNI is not supported by an IRF member device, even when the device is the only member in an

IRF fabric. Before you configure DRNI on a device, verify that it is operating in standalone mode.

MDC

Only the HPE FlexFabric 12900E Switch Series (Type X) support MDC.

You cannot use DRNI on MDCs.

GIR

Before you change a DR member device back to normal mode, execute the display drni mad

verbose command to verify that no network interfaces are in DRNI MAD DOWN state.

MAC address table

If the DR system has a large number of MAC address entries, set the MAC aging timer to a higher

value than 20 minutes as a best practice. To set the MAC aging timer, use the mac-address

timer aging command.

The MAC address learning feature is not configurable on the IPP. Do not execute the

mac-address mac-learning enable or undo mac-address mac-learning enable

command on the IPP.

ARP

If a DR interface provides Layer 3 services, a VLAN interface is configured for the VLAN that

contains the DR interface for example, do not configure the following features on the DR interface:

•

ARP active acknowledgement, configurable with the arp active-ack enable command.

•

Dynamic ARP learning limit, configurable with the arp max-learning-number command.

This restriction ensures that the DR member devices can learn consistent ARP entries.

Link aggregation

Do not configure automatic link aggregation on a DR system.

The aggregate interfaces in an S-MLAG group cannot be used as DR interfaces or IPPs.

You cannot configure link aggregation management subnets on a DR system.

When you configure a DR interface, follow these restrictions and guidelines:

•

The link-aggregation selected-port maximum and link-aggregation

selected-port minimum commands do not take effect on a DR interface.

•

If you execute the display link-aggregation verbose command for a DR interface, the

displayed system ID contains the DR system MAC address and the DR system priority.

•

If the reference port is a member port of a DR interface, the display link-aggregation

verbose command displays the reference port on both DR member devices.

Port isolation

Do not assign DR interfaces and IPPs to the same port isolation group.

CFD

Do not use the MAC address of a remote MEP for CFD tests on IPPs. These tests cannot work on

IPPs.

Smart Link

The DR member devices in a DR system must have the same Smart Link configuration.

For Smart Link to operate correctly on a DR interface, do not assign the DR interface and non-DR

interfaces to the same smart link group.

Do not assign an IPP to a smart link group.

12

You can use Smart Link on a DR system formed by the following device models:

•

HPE FlexFabric 5944 switches.

•

HPE FlexFabric 5945 switches.

•

HPE FlexFabric 12900E Switch Series.

Mirroring

If you use port mirroring together with DRNI, do not assign the source port, destination port, egress

port, and reflector port for a mirroring group to two aggregation groups. If the source port is in a

different aggregation group than the other ports, mirrored LACPDUs will be transmitted between

aggregation groups and cause aggregate interface flapping.

MAC address synchronization

Two DR member devices synchronize underlay MAC address entries over the IPL and overlay MAC

address entries through BGP EVPN.

Only the MAC address entries learned by hardware age out. Synchronized MAC address entries do

not age out. If a hardware-learned MAC address entry ages out on one DR member device, the

device requests the other DR member device to delete that MAC address entry.

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DRNI network models

Layer 2 DRNI network models

Loop prevention on a DR system

For a DR system on an underlay network, configure spanning tree to remove loops. For a DR

system on an overlay network, configure VSI-based loop detection to remove loops.

DRNI and spanning tree

Network model

You can use DRNI in conjunction with spanning tree to remove loops, as shown in Figure 5 and

Table 2.

Figure 5 Network diagram

Table 2 Deployment schemes

Scenario

Solution

Commands

Due to a DR system split,

misconnection, or

Enable spanning tree on the DR

member devices. stp global enable (system

view)

STP

Spanning tree

edge port

DR 1 DR 2

DR 3

IPL

DR 4

IPL

Server

Multichassis

aggregate link Inter-DR system

aggregate link

Keepalive

Devices not participating in

spanning tree calculation

Keepalive

14

Scenario

Solution

Commands

misconfiguration, traffic is sent

between two member ports of

the same aggregation group

over the IPL

, which creates a

loop.

Assign the spine-facing interfaces

on leaf devices to different VLANs

if the leaf and spine devices are

interconnected by using VLAN

interfaces in an EVPN distributed

relay

network. In addition, disable

spanning tree on physical

interface

s to remove loops and

prevent the upstream device from

falsely blocking interfaces.

undo stp enable (

Layer 2

Ethernet interface view)

A new device added to the

network preempts the root

bridge role, and network

flapping occurs as a result.

Configure the DR member devices

in the upstream DR system as root

bridges and enable root guard on

them.

stp root primary (system view)

stp root-protection (DR

interface view)

The DR member devices are

attacked by using TC-BPDUs

and flush MAC address entries

frequently, which causes

network flapping, high CPU

usage, and transient floods.

Enable the TC-

BPDU guard

feature on the DR member

devices.

stp tc-protection (system

view)

On a DR member

device, an

interface cannot recognize

BPDUs after its physical state

changes.

Configure an interface as an edge

port if

its peer port does not

support or run spanning tree

protocols.

stp edged-port (DR interface

view)

Network flapping occurs after a

DR member

device receives

forged BPDUs on interfaces

whose counterparts

do not

send BPDUs.

Enable BPDU guard on the DR

member device. When interfaces

with BPDU guard enabled receive

configuration BPDUs, the device

performs the following operations:

• Shuts down these interfaces.

•

Notifies the NMS that these

interface

s have been shut

down by the spanning tree

protocol.

The device re

activates the

interface

s that have been shut

down when the port status

detection timer expires.

stp bpdu-protection (system

view)

Restrictions and guidelines

Make sure the DR member devices in a DR system have the same spanning tree configuration.

Violation of this rule might cause network flapping. The configuration includes:

•

Global spanning tree configuration.

•

Spanning tree configuration on the IPP.

•

Spanning tree configuration on DR interfaces.

IPPs of the DR system do not participate in spanning tree calculation.

The DR member devices still use the DR system MAC address after the DR system splits, which

will cause spanning tree calculation issues. To avoid the issues, enable DRNI standalone mode on

the DR member devices before the DR system splits.

Spanning tree configurations made in system view take effect globally. Spanning tree configurations

made in Layer 2 Ethernet interface view take effect only on the interface. Spanning tree

configurations made in Layer 2 aggregate interface view take effect only on the aggregate interface.

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Spanning tree configurations made on an aggregation member port can take effect only after the

port is removed from its aggregation group.

After you enable a spanning tree protocol on a Layer 2 aggregate interface, the system performs

spanning tree calculation on the Layer 2 aggregate interface. It does not perform spanning tree

calculation on the aggregation member ports. The spanning tree protocol state and forwarding state

of each selected member port are consistent with those of the corresponding Layer 2 aggregate

interface. The member ports of an aggregation group do not participate in spanning tree calculation.

However, the ports still reserve their spanning tree configurations for participating in spanning tree

calculation after leaving the aggregation group.

DRNI and VSI-based loop detection

Mechanisms

As shown in Figure 6, if an endpoint is dualhomed to the DR system, you must enable loop

detection on both VTEPs in the DR system. Loop detection works as follows on the VTEPs:

1. The VTEPs send loop detection frames out of the ACs configured on the DR interfaces facing

the endpoint. The loop detection frames contain the same source MAC address, VLAN tag,

loop detection interval, and loop detection priority. The source MAC address is the DR system

MAC address.

2. When receiving loop detection frames on a local DR interface, a VTEP sends the loop

detection frames to the peer VTEP over the IPL. This synchronization mechanism ensures that

a VTEP can receive loop detection frames in case of link or interface failure.

3. If a VTEP receives a self-sent loop detection frame from an AC, the VTEP compares the loop

detection priority of the AC with that in the frame and acts as follows:

 If the loop detection priority in the frame is higher, the VTEP performs the loop protection

action on all ACs configured for the DR group that accommodates the looped DR interface.

 If the loop detection priority of the AC is higher, the system only records the loop

information.

If an endpoint is singlehomed to one VTEP in the DR system, enable loop detection only on that

VTEP. Loop detection works as follows on the VTEP:

4. The VTEP sends loop detection frames out of the ACs configured on the DR interface facing

the endpoint. The source MAC address is the DR system MAC address.

5. If the VTEP receives a self-sent loop detection frame from an AC, the VTEP compares the

loop detection priority of the AC with that in the frame and acts as follows:

 If the loop detection priority in the frame is higher, the VTEP performs the loop protection

action on the looped AC.

 If the loop detection priority of the AC is higher, the system only records the loop

information.

16

Figure 6 Loop detection in a VXLAN network with DRNI configured

Compatibility of data center switches with VSI-based loop detection

Hardware

Software

Reference

HPE FlexFabric 12900E

Switch Series (Type K) R5210 and later

See VXLAN loop detection in Layer