MC peer groups overview

Overview

An MC peer group is an NFM-P object that defines the relationship between two peer NEs to provide system redundancy in an Ethernet network. An MC peer group configuration includes a list of protocols and objects with state information that is to be synchronized between the peers.

On supporting NEs, you can create up to 20 MC peer groups using Ethernet ports in access mode. An MC peer group can contain one or more of the following child group objects:

Note: You can create MC endpoints only on a 7450 ESS, 7750 SR, or 7950 XRS.

You can create MC IPsec tunnel groups only on a 7450 ESS-4, 7450 ESS-6, 7450 ESS-6v, 7450 ESS-7, 7450 ESS-12 in mixed mode and in chassis mode D, or on a 7750 SR-7, 7750 SR-12, or 7750 SR-12E in chassis mode D.

When you create a child group object, the NFM-P automatically creates the child group members using the peer objects in the MC peer group.

The NFM-P automatically discovers MC peers that are configured on managed NEs and creates an MC peer group if the source address of each peer matches the peer address of the other. If an MC peer address on an NE is changed after discovery, for example, using a CLI, the NFM-Pdeletes the MC peer group but does not delete the peer configuration on either NE. When the mismatch is corrected, the NFM-P recreates the MC peer group.

When the MC peer addresses match but the NFM-P detects another MC peer group configuration mismatch, the NFM-P raises an alarm and displays a check mark beside the Asymmetrical Configuration Detected indicator on the General tab of the MC Peer Group properties form. The alarm information includes the type of configuration mismatch. When the mismatch is corrected, the alarm and check mark clear.

You can configure NE redundancy using the Manage Node Redundancy form or an NE properties form. When the NFM-P manages both NEs in an MC peer group, you can configure the MC peer and peer group parameters using the Manage Node Redundancy form. When the NFM-P manages only one NE in the MC peer group, you can configure the only the managed peer parameters, and only by using the NE properties form.

You can configure MC IPsec as a failover mechanism for IPsec tunnels between two 7750 SRs. MC IPsec provides protection for NE or MS-ISA failure. When the active peer fails, the IPsec tunnels failover to the standby peer without re-establishing the session. See Chapter 41, MC IPsec for more information.

OMCR on MC peer groups

You can configure the warm standby option on MC peer groups to provide oversubscribed multi-chassis redundancy, or OMCR, throughout the peer group.

In the OMCR model, a central standby NE backs up multiple subscriber hosts on multiple NEs; the subscribers are synchronized among the chassis CPMs. By avoiding subscriber host instantiation in the forwarding plane during normal operation, resources are used only as required.