Overview

Port and channel objects

Port objects are children of daughter card slot objects. They appear below the daughter card slot after the daughter card is configured. Channel objects are children of port objects. They appear on the navigation tree below the port object after the channel is configured.

Properties forms for port objects and channel objects are accessed using the NFM-P navigation tree.

This chapter contains the procedures to configure devices using the navigation tree. See Chapter 3, NFM-P navigation tree for more information about using the navigation tree.

Working with port and channel objects

The types of ports that are available depend on the daughter cards that are configured in the chassis. For some OmniSwitch devices, the ports that are available depend on the chassis type, for others the type of card that is configured for the card slot. Ethernet ports cannot be channelized. SONET/SDH and TDM ports can be channelized.

The port syntax for most devices that support daughter cards is card slot/daughtercard/port. For example, Port 1/1/1 represents port 1 of daughter card 1 in slot 1. Connector ports are indicated in the equipment tree by the letter c preceding the port number; for example, 1/1/c1/1. The port syntax for the OmniSwitch is card slot/port.

In most cases, ports are created automatically when the daughter card is created. You must select one port object at a time and configure the properties of the port for the service that you need the port to provide. The properties vary depending on the port type. Channel objects are created on SONET/SDH or TDM ports for any type of channelization on the port whether it is a clear channel application or a sub-channel application.

Use the properties forms from the contextual menus in the navigation tree to configure port and channel parameters. You can configure the port mode as network, access, or hybrid.

Note: By default, a port is in network mode.

See To change the port mode to change the port mode.

Clear channel ports (OC-192/OC-48c/OC-12c/OC-3c) are network or access ports. Channelized ports (CHOC-12/CHOC-3c/ DS3/E3) are always in access mode, however, the ASAP CHOC-3 supports both access and network modes. The ASAP DS1/E1 ports support:

Network ports are used in the service provider transport or infrastructure network, such as an IP/MPLS-enabled backbone network or uplink ports for rings using L2 Ethernet switches. A port that is in network mode can be assigned an IP address and host an L3 interface that can perform IP routing functions.

Access ports are associated with a SAP, a subscriber, and a service to provide connectivity. Access ports and channels are configured with encapsulation values to differentiate the service on the port or channel. When a port is access mode, one or more services can be configured on the port. A channelized port that is to act as an endpoint must be in access mode. You can convert access ports to hybrid ports and migrate any existing SAPs. See To migrate SAPs from access mode to hybrid mode for more information.

Hybrid ports are ports that can host SAPs and network interfaces simultaneously. This enables a customer to use one uplink port for enterprise and end-user traffic. A hybrid port preserves the existing network and access port functionality, and uses the same QoS, scheduler, and port scheduler resources as other ports, but requires the configuration of weight values that allocate buffer percentages to the access and network traffic on the port.

The NFM-P supports hybrid mode configuration on Ethernet ports. Support for hybrid ports varies depending on the NE chassis, card, and release; see the NE documentation for information.

Note: Single-slot chassis such as the 7450 ESS-1 and 7750 SR-1 do not support hybrid port mode.

You can configure a hybrid port on an Ethernet MDA in an IOM-3XP, or on a CMA in an IOM-XP. The 7750 SR supports hybrid port configuration on an IMM in addition to an IOM-3XP.

Note: Hybrid port configuration is not supported on an HSMDA or a VSM MDA.

A hybrid port supports dot1q and QinQ encapsulation, but does not support null encapsulation, in order to accommodate single-SAP operation. The available VLAN tags are shared among the VLAN SAPs and VLAN network IP interfaces. When you create a SAP or L3 interface on a hybrid port, the outer VLAN tag must not be in use by another SAP or L3 interface on the port.

By default, the MTU of a hybrid port is set to the larger of the network and access MTUs to accommodate the creation of L3 interfaces and SAPs.

Note: A hybrid port can participate in a single-chassis LAG.

A hybrid port cannot participate in an MC-LAG or MC ring.

See the appropriate device documentation for more information about hybrid ports.

When working with a TDM port, you must specify the Line Buildout as either short or long. That is, for a DS3 port the Line Buildout parameter must be configured. If the TDM port is in the context of a SONET STS-1 sub-channel, for example, the DS3 channel is built on the STS-1 channel of a SONET port, the line buildout parameter is not required.

At the connection termination points, you are required to configure the Encap Type as required, the MTU size as required, and the configured MAC address as required when configuring the port or channel.

Policies can be added or deleted as required using the manage policy forms.

You can associate policies to ingress and egress access and network ports. Buffer policies are used to create and edit QoS buffer pool resources on network ports, access ports, and access channels. Egress network ports, access ports, and access channels have a dedicated buffer pool for queuing. The traffic is handled by a single buffer pool, one at the ingress, and one at the egress.

You can configure the amount of egress buffer space to be allocated to the port or channel. By default, all egress buffers are allocated fairly among the egress ports and channels based on their relative egress bandwidth.

The egress buffers for egress network ports and channels are put into per-port or per-channel egress buffer pools and are used by the egress network forwarding class queues on that port or channel. The ingress buffers allocated to network ports and channels are summed into a single pool and are used by the ingress network forwarding class queues (defined by the network ingress buffer policy).

The egress and ingress buffers allocated to access ports and channels are put into an egress buffer pool and ingress buffer pool for the port or channel. The access buffer pools are used by egress and ingress service queues created by the SAP-egress and SAP-ingress policies in use by services on the port or channel.

Changing the size of an egress buffer pool should be carefully planned. By default, there are no free buffers to increase the size of a pool. In order to increase a pool on one port or channel, the same amount of buffers must be freed from other egress buffer pools on the same daughter card.