User manual
Table Of Contents
- Cisco ONS 15310-CL and Cisco ONS 15310-MA Ethernet Card Software Feature and Configuration Guide
- Contents
- Preface
- Overview of the ML-Series Card
- CTC Operations on the ML-Series Card
- Initial Configuration of the ML-Series Card
- Configuring Interfaces on the ML-Series Card
- Configuring POS on the ML-Series Card
- Configuring STP and RSTP on the ML-Series Card
- STP Features
- STP Overview
- Supported STP Instances
- Bridge Protocol Data Units
- Election of the Root Switch
- Bridge ID, Switch Priority, and Extended System ID
- Spanning-Tree Timers
- Creating the Spanning-Tree Topology
- Spanning-Tree Interface States
- Spanning-Tree Address Management
- STP and IEEE 802.1Q Trunks
- Spanning Tree and Redundant Connectivity
- Accelerated Aging to Retain Connectivity
- RSTP Features
- Interoperability with IEEE 802.1D STP
- Configuring STP and RSTP Features
- Default STP and RSTP Configuration
- Disabling STP and RSTP
- Configuring the Root Switch
- Configuring the Port Priority
- Configuring the Path Cost
- Configuring the Switch Priority of a Bridge Group
- Configuring the Hello Time
- Configuring the Forwarding-Delay Time for a Bridge Group
- Configuring the Maximum-Aging Time for a Bridge Group
- Verifying and Monitoring STP and RSTP Status
- STP Features
- Configuring VLANs on the ML-Series Card
- Configuring IEEE 802.1Q Tunneling and Layer 2 Protocol Tunneling on the ML-Series Card
- Configuring Link Aggregation on the ML-Series Card
- Configuring IRB on the ML-Series Card
- Configuring Quality of Service on the ML-Series Card
- Understanding QoS
- ML-Series QoS
- QoS on RPR
- Configuring QoS
- Monitoring and Verifying QoS Configuration
- QoS Configuration Examples
- Understanding Multicast QoS and Multicast Priority Queuing
- Configuring Multicast Priority Queuing QoS
- QoS not Configured on Egress
- ML-Series Egress Bandwidth Example
- Understanding CoS-Based Packet Statistics
- Configuring CoS-Based Packet Statistics
- Understanding IP SLA
- Configuring the Switching Database Manager on the ML-Series Card
- Configuring Access Control Lists on the ML-Series Card
- Configuring Resilient Packet Ring on the ML-Series Card
- Understanding RPR
- Configuring RPR
- Connecting the ML-Series Cards with Point-to-Point STS Circuits
- Configuring CTC Circuits for RPR
- Configuring RPR Characteristics and the SPR Interface on the ML-Series Card
- Assigning the ML-Series Card POS Ports to the SPR Interface
- Creating the Bridge Group and Assigning the Ethernet and SPR Interfaces
- RPR Cisco IOS Configuration Example
- Verifying Ethernet Connectivity Between RPR Ethernet Access Ports
- CRC Threshold Configuration and Detection
- Monitoring and Verifying RPR
- Add an ML-Series Card into an RPR
- Delete an ML-Series Card from an RPR
- Cisco Proprietary RPR KeepAlive
- Cisco Proprietary RPR Shortest Path
- Redundant Interconnect
- Configuring Security for the ML-Series Card
- Understanding Security
- Disabling the Console Port on the ML-Series Card
- Secure Login on the ML-Series Card
- Secure Shell on the ML-Series Card
- RADIUS on the ML-Series Card
- RADIUS Relay Mode
- RADIUS Stand Alone Mode
- Understanding RADIUS
- Configuring RADIUS
- Default RADIUS Configuration
- Identifying the RADIUS Server Host
- Configuring AAA Login Authentication
- Defining AAA Server Groups
- Configuring RADIUS Authorization for User Privileged Access and Network Services
- Starting RADIUS Accounting
- Configuring a nas-ip-address in the RADIUS Packet
- Configuring Settings for All RADIUS Servers
- Configuring the ML-Series Card to Use Vendor-Specific RADIUS Attributes
- Configuring the ML-Series Card for Vendor-Proprietary RADIUS Server Communication
- Displaying the RADIUS Configuration
- Configuring Bridging on the ML-Series Card
- CE-100T-8 Ethernet Operation
- Command Reference for the ML-Series Card
- [no] bridge bridge-group-number protocol {drpri-rstp | ieee | rstp}
- clear counters
- [no] clock auto
- interface spr 1
- [no] pos mode gfp [fcs-disabled]
- [no] pos pdi holdoff time
- [no] pos report alarm
- [non] pos trigger defects condition
- [no] pos trigger delay time
- [no] pos vcat defect {immediate | delayed}
- show controller pos interface-number [details]
- show interface pos interface-number
- show ons alarm
- show ons alarm defect {[eqpt | port [port-number] | sts [sts-number] | vcg [vcg-number] | vt]}
- show ons alarm failure {[eqpt | port [port-number] | sts [sts-number] | vcg [vcg-number] | vt]}
- spr-intf-id shared-packet-ring-number
- [no] spr load-balance { auto | port-based }
- spr station-id station-id-number
- spr wrap { immediate | delayed }
- Unsupported CLI Commands for the ML-Series Card
- Using Technical Support
- Index

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Chapter 6 Configuring STP and RSTP on the ML-Series Card
STP Features
Creating the Spanning-Tree Topology
In Figure 6-1, Switch A is elected as the root switch because the switch priority of all the switches is set
to the default (32768) and Switch A has the lowest MAC address. However, because of traffic patterns,
number of forwarding interfaces, or link types, Switch A might not be the ideal root switch. By
increasing the priority (lowering the numerical value) of the ideal switch so that it becomes the root
switch, you force a spanning-tree recalculation to form a new topology with the ideal switch as the root.
Figure 6-1 Spanning-Tree Topology
When the spanning-tree topology is calculated based on default parameters, the path between source and
destination end stations in a switched network might not be ideal. For instance, connecting higher-speed
links to an interface that has a higher number than the root port can cause a root-port change. The goal
is to make the fastest link the root port.
Spanning-Tree Interface States
Propagation delays can occur when protocol information passes through a switched LAN. As a result,
topology changes can take place at different times and at different places in a switched network. When
an interface transitions directly from nonparticipation in the spanning-tree topology to the forwarding
state, it can create temporary data loops. Interfaces must wait for new topology information to propagate
through the switched LAN before starting to forward frames. They must allow the frame lifetime to
expire for forwarded frames that have used the old topology.
Each Layer 2 interface on a switch using spanning tree exists in one of these states:
• Blocking—The interface does not participate in frame forwarding.
• Listening—The first transitional state after the blocking state when the spanning tree determines
that the interface should participate in frame forwarding.
• Learning—The interface prepares to participate in frame forwarding.
• Forwarding—The interface forwards frames.
• Disabled—The interface is not participating in spanning tree because of a shutdown port, no link on
the port, or no spanning-tree instance running on the port.
An interface moves through these states:
1. From initialization to blocking
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