Junos Space Ethernet Interfaces Overview

A Junos Space Appliance has four Ethernet interfaces; three interfaces can be used and one is reserved for future use. The Ethernet interfaces are labeled ETH0, ETH1, ETH2, and ETH3 for the JA1500 Junos Space Appliance, and 0, 1, 2, and 3 for the JA2500 Junos Space Appliance.

The Ethernet interfaces eth0 and eth3 support both IPv4 and IPv6 addresses. As a separate IP address is available for each IP stack, for any connection initiated by Junos Space, the source IP address (that is, the IPv4 or IPv6 address) of the connection is bound by the IP address type of a managed device. For a connection initiated by a managed device, Junos Space listens on both IPv4 and IPv6 addresses of the device management interface (eth3). Therefore, a managed device can communicate with Junos Space by using its IPv4 or IPv6 address.

Note:

From Junos Space Network Management Platform Release 14.1R2 onward, you can configure Junos Space Ethernet interfaces with only IPv4 addresses, or both IPv4 and IPv6 addresses.

Note:

Starting in Junos Space Network Management Platform Release 21.1R1, Ethernet interface order is changed for the JA2500 Junos Space Appliance.

Physical Ethernet connection in the JA2500 appliance needs to be altered as below:

1. Cable in eth0 needs to be connected to eth3 port that is as per notations on the JA2500 appliance front panel 3.

2. Cable in eth1 needs to be connected to eth2 port that is as per notations on the JA2500 appliance front panel 2.

3. Cable in eth2 needs to be connected to eth1 port that is as per notations on the JA2500 appliance front panel 1.

4. Cable in eth3 needs to be connected to eth0 port that is as per notations on the JA2500 appliance front panel 0.

Junos Space supports managed devices based on the IP address type (that is, the IPv4 or IPv6 address) configured for the device management interface. You can configure an IPv4 or IPv6 address for the device management interface. If the device management interface is not configured, the IP address type of the node management interface (eth0) is considered for communication with managed devices.Table 1 details the support matrix for IPv4 and IPv6 address configurations on the device management interface.

Table 1: Matrix for IP Address Versions Supported on Devices

eth0		eth3		IP Address of Managed Devices Supported by Junos Space
IPv4 Address	IPv6 Address	IPv4 Address	IPv6 Address
Configured	Not Configured	Not Configured	Not Configured	IPv4
Configured	Configured	Not Configured	Not Configured	IPv4 and IPv6
Configured	Not Configured	Configured	Not Configured	IPv4
Configured	Not Configured	Configured	Configured	IPv4 and IPv6
Configured	Not Configured	Not Configured	Configured	IPv6
Configured	Configured	Configured	Configured	IPv4 and IPv6

You can use the Ethernet interfaces as follows:

• eth0—Use the eth0 interface to configure the virtual IP (VIP) address of a fabric and the IP address of the node as well as to access the managed devices. The VIP address and the IP address of the node should be on the same subnet.

  The eth0:0 subinterface provides access to the Junos Space Network Management Platform GUI. You can access the GUI by using the VIP address of the fabric.

• eth1—Use the eth1 interface as an administrative interface of a Junos Space node. Use SSH to access a Junos Space node through this interface. The eth0 interface and the eth1 interface can be on different subnets.

  If you configure eth1, you cannot access the Junos Space nodes using the eth0 interface. You can access the CLI of the Junos Space node only through the eth1 interface.

• eth2—The eth2 interface is reserved for future use.

• eth3—Use the eth3 interface as the device management interface for SSH access to managed devices when the managed devices are on an out-of-band management subnet or on a subnet not accessible through the eth0 interface.

  Note:

  • If the managed devices are not accessible through the default gateway, you must configure static routes. Any static route configured manually is populated in the main routing table, which is used to route traffic through the eth0 interface.

  • When the eth3 interface is configured as a device management interface, Junos Space Platform does not forward ICMP packets through the eth3 interface. To allow ICMP packets through the eth3 interface, routes must be added manually.

• When you configure an appliance as a Junos Space node, you can configure the Ethernet interfaces as follows:

  • Configure only the eth0 interface.

    When only Ethernet interface (eth0) is used, the Junos Space nodes in the fabric, virtual IP (VIP) address of the fabric, and the devices being managed by Junos Space are on the same subnet.

  • Configure the eth0 and eth3 interfaces.

    When Ethernet interfaces eth0 and eth3 are used, the Junos Space nodes in the fabric and VIP address of the fabric are on the same subnet and are reachable through Ethernet interface ETH0 (JA1500 appliance) or Ethernet interface 0 (JA2500 appliance). The devices being managed by Junos Space are on the same subnet, which is different from the one reachable through Ethernet interface ETH0 or Ethernet interface 0, and are reachable through Ethernet interface ETH3 (JA1500 appliance) or Ethernet interface 3 (JA2500 appliance).

  • Configure the eth0 and eth1 interfaces.

    When Ethernet interfaces eth0 and eth1 are used, the Junos Space nodes in the fabric and the VIP address of the fabric may or may not be on the same subnet. The eth1 interface provides SSH access to the Junos Space nodes.

    The VIP address and the devices being managed by Junos Space are on the same subnet.

  • Configure the eth0, eth1, and eth3 interfaces.

    When Ethernet interfaces eth0, eth1, and eth3 are used, the Junos Space nodes in the fabric and the VIP address of the fabric may or may not be on the same subnet. The Junos Space nodes are reachable (SSH access) only through the eth1 interface.

    The managed devices can be reached through the eth0 interface if they are configured on the same subnet as the VIP address; on any other subnet, the managed devices can be reached through the eth3 interface.

    Note:

    If the managed devices are not reachable through the default gateway configured for the eth3 interface, you must configure static routes for the eth3 interface. The eth3 interface refers to the devint routing table.

    Any static route configured manually is populated in the main routing table, which is used to route traffic through the eth0 interface.

• When you configure an appliance as a specialized node used for fault monitoring and performance monitoring (FMPM), you can use only the Ethernet interfaces eth0 and eth1.

  Ethernet interface eth1 provides SSH access to FMPM nodes.

Note:

For more information about the Junos Space fabric, refer to the Managing Nodes in the Junos Space Fabric chapter in the Junos Space Network Management Platform Workspaces Feature Guide (available at http://www.juniper.net/documentation/en_US/release-independent/junos-space/index.html).

Table 2 summarizes the functions of Ethernet interfaces on the Junos Space Appliance.

Table 2: Junos Space Appliance Ethernet Interfaces

Interface	Function
ETH0 or 3	SSH and device management, if only the Ethernet interface ETH0 or Ethernet interface 0 is used
ETH0:0 or 3:0	GUI interface
ETH1 or 2	SSH access to the Junos Space nodes Note: SSH is disabled on the eth0 and eth3 interfaces when eth1 is configured.
ETH2 or 1	Reserved for future use
ETH3 or 0	Device management when managed devices are on an out-of-band management subnet and not reachable by the Ethernet interface eth0