Support - 29-IRF Fabric Operation (2024)

1.1 Overview

1.1.1 Introduction to IRF

Several IRF (intelligent resilientframework) supported switches of the same model can be interconnected to form afabric, in which each switch is a unit. The ports used to interconnect all theunits are called fabric ports, and the other ports that are used to connect thefabric to users are called user ports. In this way, you can increase ports andswitching capability by adding devices to the fabric. In addition, reliabilityof the system will be improved because the devices within the fabric can backupeach other. This feature brings you many advantages:

lRealizes unified management of multiple devices.Only one connection and one IP address are required to manage the entirefabric. Therefore, management cost is reduced.

lEnables you to purchase devices on demand andexpand network capacity smoothly. Protects your investment to the full extentduring network upgrade.

lEnsures high reliability by N+1 redundancy,avoids single point failure, and lessens service interruption.

Figure 1-1 Fabric

You can manage and maintain fabric topologywith the Fabric Topology Management (FTM) function. FTM on each unit exchangesinformation with other units, including unit ID, fabric name, and theauthentication mode between units, by using a special kind of protocol packets.It manages and maintains fabric topology according to the acquired information.For example, when a new device is connected to a fabric, FTM will determinewhether it should establish a new fabric with the device according to theobtained information.

1.1.2 Introductionto RMON on IRF

The RMON configurations of the devices in afabric are the same. The RMON configuration performed on a device of a fabricwill be automatically synchronized to all devices in the fabric if theconfiguration does not conflict with that of other devices in the fabric.

If you configure the same entry in the sameRMON group for devices of a fabric to be different values, the value of theRMON group entry will be the one configured by the device with the smallestUnit ID when the devices are synchronized. Such a mechanism eliminatesconfiguration conflicts between the devices in a fabric.

After the configurations are consistent,you can collect RMON history and statistics of any unit from any switch in thefabric.

1.2 Peer Fabric Port Detection

1.2.1 Introduction to the Peer Fabric PortDetection Function

As the basis of the IRF function, thefabric topology management (FTM) module manages and maintains the entiretopology of a fabric. The FTM module also implements the peer fabric portdetection function.

A device can join a fabric only when thefollowing conditions are met.

lThe number of the existing devices in the fabricdoes not reach the maximum number of devices allowed by the fabric.

lThe fabric names of the device and the existingdevices in the fabric are the same.

lThe software version of the device is the sameas that of the existing devices in the fabric.

lThe device passes the security authentication ifsecurity authentication is enabled in the fabric.

1.2.2 Work Flowof the Peer Fabric Port Detection Function

After a switch is powered on, the FTMmodule releases device information of the switch through the fabric ports. Thedevice information includes Unit ID, CPU MAC, device type ID, fabric portinformation, and all fabric configuration information. The device informationis released in the form of discovery packet (DISC). A new device can join afabric only when its DISC packets pass the authentication performed by theexisting devices in the fabric.

lIf a fabric port of a switch is connected to anon-fabric port, the switch will not receive DISC packets from the peer. Inthis case, the switch cannot join the fabric.

lIf the switch can receive DISC packets sent bythe peer, the FTM module determines whether peer sending ports correspond tolocal receiving ports according to information in the packet. That is, if aDISC packet received by the left port of the switch is sent by the right portof the peer device, the packet is regarded legal. Otherwise, the packet isregarded illegal and is discarded.

lIf the maximum number of devices allowed by thefabric is reached, the devices in the fabric do not send DISC packets anddiscard the received DISC packets. This prevents new devices from joining thefabric.

lAfter receiving a DISC packet from a directlyconnected device, a device in a fabric checks whether the device information(that is, the Fabric name and software version) contained in the packet and thatof its own are the same. If not, the received DISC packet is illegal and willbe discarded.

lIf authentication is enabled in the fabric, thecurrent device in the fabric authenticates received packets sent by newdirectly connected devices. Packets that fail to pass the authentication willbe discarded.

1.2.3 PromptInformation and Solution

I. Normal

If the port displays “normal”,it indicates the fabric operates properly.

II. Temporary

If the port displays“temporary”, it indicates the port status is changing.

III. Redundance port

If the port displays “redundanceport”, it indicates the port is the redundant port in a fabric ringtopology.

& Note:

The“normal”, “temporary” and “redundance port”information does not mean a device or a fabric operates improperly. No measureis needed for any of these three types of information.

IV. Connection error

Analysis: The port matching errors (aslisted in Table 1-1) may occur if a switch prompts the “connection error”message.

Solution: Take the measures listed in Table 1-1 accordingly.

Table 1-1 Connection error type and solution

V. Reached max units

Analysis: The “reached maxunits” message indicates that the maximum number of units allowed by thecurrent fabric is reached. You will fail to add new devices to the fabric inthis case.

Solution: Remove the new device or existingdevices in the fabric.

& Note:

Up to eight devicescan be in an IRF fabric at a time.

VI. Different system name

Analysis: The “different systemname” message indicates the fabric name of the device directly connectedto the switch and the existing fabric name of the fabric are not the same. Onlythe devices with the same fabric name can form a Fabric.

Solution: Configure the fabric name of thenew device to be that of the fabric.

VII. Different product version

Analysis: The “different productversion” message indicates the software version of the directly connecteddevice and that of the current device are not the same. A device can join afabric only when its software version is identical to that of the fabric.

Solution: Make sure the software version ofthe new device is the same as that of the fabric.

VIII. Auth failure

Analysis: The “auth failure”message indicates error occurs when the switch authenticates a directlyconnected device. The error may occur if the IRF fabric authentication modesconfigured for both devices are not the same, or the password configured doesnot match.

Solution: Make sure the IRF fabricauthentication modes and the passwords configured for both devices are thesame.

1.3 IRF FabricConfiguration

1.3.1 Introduction to IRF Fabric Configuration

FTM provides user interfaces. You canconfigure VLAN, unit IDs, fabric name, and the authentication mode betweenunits by using a related command.

Table 1-2 Configurean IRF Fabric

1.3.2 Specifying the VLAN Used to Form an IRFFabric

Table 1-3 Specifythe VLAN used to form an IRF fabric

Caution:

You cannot specifyan existing VLAN to form an IRF fabric; otherwise, your configuration fails.

1.3.3 Setting a Unit ID for a Switch

On the switches that support automaticnumbering, FTM will automatically number the switches to constitute an IRFfabric, so that each switch has a unique unit ID in the fabric. You can use thecommand in the following table to set unit IDs for switches. Make sure to setdifferent unit IDs for different switches in an IRF fabric. Otherwise, FTM willautomatically number the switches with the same unit ID.

Table 1-4 Seta unit ID for a switch

If you do notenable the fabric port, you cannot change the unit ID of the local switch.

After an IRF fabric is established, you canuse the following command to change the unit IDs of the switches in the IRFfabric.

Table 1-5Set a unit ID to a new value

& Note:

After you change the unit ID of switches,the following operations are performed.

lIf the modified unit ID does not exist in the IRFfabric, the system sets its priority to 5 and saves it in the unit Flashmemory.

lIf the modified unit ID is an existing one, thesystem prompt you to confirm if you really want to change the unit ID. If youchoose to change, the existing unit ID is replaced and the priority is set to5. Then you can use the fabric save-unit-id command to save the modifiedunit ID into the unit Flash memory and clear the information about the existingone.

lIf auto-numbering is selected, the systemsets the unit priority to 10. You can use the fabric save-unit-idcommand to save the modified unit ID into the unit Flash memory and clear theinformation about the existing one.

& Note:

Priority is thereference for FTM module to perform automatic numbering. The value of prioritycan be 5 or 10. A smaller value represents a higher priority. Priority 5 meansthe switch adopts manual numbering, and priority 10 means the switch adoptsautomatic numbering.

After the configuration of numbering, youcan use the following command in the table to save the local unit ID in theunit Flash memory. When you restart the switch, it can load the unit IDconfiguration automatically.

Table 1-6Save the unit ID of each unit in the IRF fabric

1.3.4 Specifying the Fabric Port of a Switch

The fabric port of an S3600 series Ethernetswitch has the following features:

lAn S3600 series Ethernet switch has four GigabitEthernetports that can be used as fabric ports. The four ports fall into two groupsaccording to the port number. GigabitEthernet1/1/1 and GigabitEthernet1/1/2form the first group, and GigabitEthernet1/1/3 and GigabitEhternet1/1/4 formthe second group.

lOnly one group of ports can be the fabric portsat a time. GigabitEthernet1/1/1 and GigabitEthernet1/1/3 are the UP standbyfabric port of their respective group. GigabitEthernet1/1/2 andGigabitEthernet1/1/4 are the DOWN standby fabric port of their respectivegroup.

lThe system has no restriction on the fabric portgroup. That is, if the local end uses the fabric port in the first group, itcan connect to the fabric port in either the first or the second group of thepeer end. As long as meeting the conditions introduced in section 1.2.1 , the switches can establish an IRF fabric connection successfully.

You can use the fabric port commandto enable a fabric port. At the same time, the group where this fabric portresides becomes the fabric port group, and the other port in the group will beautomatically enabled with fabric port feature. For example, after the fabricport GigabitEthernet1/1/1 enable command is executed, portGigabitEthernet1/1/1 becomes the UP fabric port. At the same time, the firstgroup becomes the fabric port group, and the other port GigabitEthernet1/1/2 inthe first group becomes DOWN fabric port automatically.

You can specify a port as a fabric port by executing the command in Table 1-7.

Table 1-7 Specify a fabric port

& Note:

1.3.5 Assigninga Unit Name to a Switch

You can assign a unit name to a switch byperforming the operations listed in Table 1-8.

Table 1-8 Assign a unit name to a switch

1.3.6 Assigning anIRF Fabric Name to a Switch

Only the switches with the same IRF fabricname can form an IRF fabric.

Table 1-9Assign a fabric name to a switch

1.3.7 Setting theIRF Fabric Authentication Mode

Only the switches with the same IRF fabric authenticationmode can form an IRF fabric.

Table 1-10 Set the IRF fabric authentication mode for a switch

& Note:

When an IRF fabric operatesnormally, you can regard the whole fabric as a single device and performconfiguration on it. Multiple switches constitute an IRF fabric. Therefore,data transmission and simultaneous program execution among the switches maycause the IRF fabric in a busy situation. When you configure the IRF fabric,you may receive a prompt “Fabric system is busy, please trylater…” which indicates the fabric system does not perform yourconfiguration properly. In this case, you need to verify your previous configurationor perform your configuration again.

1.4 Displayingand Debugging IRF Fabric

Following completion of the aboveconfiguration, you can execute the display command in any view to viewdevice management and verify the settings. And you can execute the resetcommand to clear the FTM statistics.

Table 1-11 Display and debug FTM

1.5 IRF FabricConfiguration Example

1.5.1 Network Requirements

Configure unit ID, unit name, IRF fabricname, and authentication mode for four switches to enable them to form an IRFfabric.

The configuration details are as follows:

lUnit IDs: 1, 2, 3, 4

lUnit names: unit 1, unit 2, unit 3, unit 4

lFabric name: hello

lAuthentication mode: simple password

lPassword: welcome

1.5.2 Network Diagram

Figure 1-2 Network diagram for forming an IRF fabric

1.5.3 Configuration Procedure

1)Configure Switch A.

# Configure the unit ID as 1.

<H3C> system-view

[H3C] change unit-id 1 to 1

# Configure the unit name as unit 1.

[H3C] set unit 1 name unit1

# Configure the fabric name as hello.

[H3C] sysname hello

# Configure the authentication mode as simplepassword and the password as welcome.

[hello] irf-fabricauthentication-mode simple welcome

2)Configure Switch B.

# Configure the unit ID as 2.

<H3C> system-view

[H3C] change unit-id 1 to 2

# Configure the unit name as unit 2.

[H3C] set unit 1 name unit2

# Configure the fabric name as hello.

[H3C] sysname hello

# Configure the authentication mode assimple password and the password as welcome.

[hello] irf-fabricauthentication-mode simple welcome

Configurations on Switch C and Switch D aresimilar with the above configurations.