What Happens When You Enable Chassis Cluster

After wiring the two devices together as described in Hardware Setup for SRX Series Chassis Clusters or Hardware Setup for J Series Chassis Clusters, you use CLI operational mode commands to enable chassis clustering by assigning a cluster ID and node ID on each chassis in the cluster. The cluster ID is the same on both nodes.

To do this, you connect to the console port on the device that will be the primary, give it a node ID, and identify the cluster it will belong to, then reboot the system. You then connect the console port to the other device, give it a node ID, and assign it the same cluster ID you gave to the first node, then reboot the system. In both instances, you can cause the system to boot automatically by including the reboot parameter in the CLI command line. (For further explanation of primary and secondary nodes, see Understanding Redundancy Groups.)

Warning: After fabric interfaces have been configured on a chassis cluster, removing the fabric configuration on either node will cause the redundancy group 0 (RG0) secondary node to move to a disabled state. (Resetting a device to the factory default configuration removes the fabric configuration and thereby causes the RG0 secondary node to move to a disabled state.) After the fabric configuration is committed, do not reset either device to the factory default configuration.

Figure 176 shows how the FPC slots are numbered on two nodes in an SRX5000 line chassis cluster. Other figures show slot numbering on both nodes in other SRX Series chassis clusters. Figure 181 shows how the PIM slots are numbered on two nodes in a J Series chassis cluster.

This topic includes:

• Node Interfaces on SRX Series Chassis Clusters
• Node Interfaces on J Series Chassis Clusters
• Management Interfaces
• Fabric Interface
• Control Interfaces
• Related Topics

Node Interfaces on SRX Series Chassis Clusters

Normally, on SRX Series devices, the built-in interfaces are numbered as follows:

For chassis clustering, most SRX Series devices have a built-in management interface named fxp0. For SRX210 devices, there is no management interface; the console connection is the best connection to reach both devices.

For the SRX5000 line, control interfaces are configured on SPCs. For the SRX3000 line and the SRX650 and SRX240 devices, control interfaces are dedicated Gigabit Ethernet ports. For SRX210 devices, fe-0/0/7 is used for the control interface.

After the devices are connected as a cluster, the slot numbering on one device and thus the interface numbering will change. The slot number for each slot in both nodes is determined using the following formula:

cluster slot number = (node ID * maximum slots per node) + local slot number

Table 160 shows an example of how slots on one device will be renumbered and one interface renamed in Node 1 for SRX Series chassis clusters.

Table 160: SRX Series Chassis Cluster Slot Numbering and Interface Naming Example

Note: See the appropriate Services Gateway Hardware Guide for details about SRX Series devices. The JUNOS Software Interfaces and Routing Configuration Guide provides a full discussion of the interface naming convention.

After you enable chassis clustering, the two chassis joined together cease to exist as individuals and now represent a single system. As a single system, the cluster now has twice as many slots. (See Figure 176, Figure 177, Figure 178, Figure 179, and Figure 180.)

Figure 176: FPC Slot Numbering in an SRX Series Chassis Cluster (SRX5800 Devices)

Note: SRX5600 and SRX5800 devices have Flex I/O Cards (flex IOCs) that have two slots to accept the following port modules: SRX-IOC-4XGE-XFP 4-Port XFP SRX-IOC-16GE-TX 16-Port RJ-45 SRX-IOC-16GE-SFP 16-Port SFP You can use these port modules to add from 4 to 16 Ethernet ports to your SRX Series device. Port numbering for these modules is slot/port module/port where slot is the number of the slot in the device in which the flex IOC is installed; port module is 0 for the upper slot in the flex IOC or 1 for the lower slot when the card is vertical, as in an SRX5800 device; and port is the number of the port on the port module. When the card is horizontal, as in an SRX5600 device, port module is 0 for the left-hand slot or 1 for the right-hand slot. For more information, see the Services Gateway Hardware Guide for your specific SRX Series model.

Figure 177: Slot Numbering in an SRX Series Chassis Cluster (SRX3400 Devices)

Figure 178: Slot Numbering in an SRX Series Chassis Cluster (SRX650 Devices)

Figure 179: Slot Numbering in an SRX Series Chassis Cluster (SRX240 Devices)

Figure 180: Slot Numbering in an SRX Series Chassis Cluster (SRX210 Devices)

Node Interfaces on J Series Chassis Clusters

Normally, on J Series devices, the built-in interfaces are numbered as follows:

After you enable chassis clustering and reboot the system, two of the built-in interfaces are repurposed as the management and control interfaces and are automatically renamed fxp0 and fxp1, respectively.

After the devices are connected as a cluster, the slot numbering and thus the interface numbering will change for one device. The cluster determines the slot number for each slot in both nodes using the following formula:

cluster slot number = (node ID * maximum slots per node) + local slot number

Table 161 shows how these interfaces are renamed and how they are renumbered for a chassis cluster for the various J Series devices.

Table 161: J Series Chassis Cluster Slot Numbering and Interface Naming Example

Note: See the J Series Services Routers Hardware Guide for details about J Series devices. The JUNOS Software Interfaces and Routing Configuration Guide provides a full discussion of the interface naming convention.

After you enable chassis clustering, the two chassis joined together cease to exist as individuals and now represent a single system. As a single system, the cluster now has twice as many PIM slots. (See Figure 181.)

Figure 181: PIM Slot Numbering in a J Series Chassis Cluster (J6350 Devices)

Management Interfaces

Note: The SRX210 device does not have any management interface.

The fxp0 interfaces function like standard management interfaces on SRX Series and J Series devices and allow network access to each node in the cluster. You must, however, first connect to each node through the console port and assign a unique IP address to each fxp0 interface.

Fabric Interface

The fabric is the data link between the nodes and is used to forward traffic between the chassis. Traffic arriving on a node that needs to be processed on the other is forwarded over the fabric data link. Similarly, traffic processed on a node that needs to exit through an interface on the other node is forwarded over the fabric. The fabric also provides for synchronization of session state objects created by operations such as authentication, Network Address Translation (NAT), Application Layer Gateways (ALGs), and IP Security (IPsec) sessions. For most SRX Series chassis clusters and for J Series chassis clusters, the fabric link can be any pair of Ethernet interfaces spanning the cluster.

Control Interfaces

The control interfaces provide the control link between the two nodes in the cluster and are used for routing updates and for control plane signal traffic, such as heartbeat and threshold information that triggers node failover. The control link is also used to synchronize the configuration between the nodes. When you submit configuration statements to the cluster, the configuration is automatically synchronized over the control link.

Related Topics

• Understanding Chassis Cluster Formation
• Understanding the Control Plane
• Understanding the Data Plane
• Disabling Chassis Cluster