Cisco ONS 15310-CL and Cisco ONS 15310-MA Ethernet Card Software Feature and Configuration Guide, Release 8.5.4
Chapter 13, Configuring the Switching Database Manager on the ML-Series Card

Table Of Contents

Configuring the Switching Database Manager on the ML-Series Card

Understanding the SDM

Understanding SDM Regions

Configuring SDM

Configuring SDM Regions

Configuring Access Control List Size in TCAM

Monitoring and Verifying SDM


Configuring the Switching Database Manager on the ML-Series Card


This chapter describes the switching database manager (SDM) features built into the ML-Series card and contains the following major sections:

Understanding the SDM

Understanding SDM Regions

Configuring SDM

Monitoring and Verifying SDM

Understanding the SDM

The ONS 15310-CL and ONS 15310-MA ML-Series card features high-speed forwarding. The ML-Series card does Layer 2 MAC address lookups through a hash table. Quality of service (QoS) classifier lookup are done in software and all other lookups are supported by the main policy engine. The ONS 15310-CL and ONS 15310-MA ML-Series card does not use external ternary content-addressable memory (TCAM) like the ONS 15454 ML-Series card.

The SDM is the software subsystem that manages the switching information. It organizes the switching information into application-specific regions and configures the size of these application regions. SDM enables exact-match and longest-match address searches, which result in high-speed forwarding.

A location index is associated with each packet forwarded and conveyed to the forwarding engine. The forwarding engine uses this location index to derive information associated with each forwarded packet.

Understanding SDM Regions

SDM partitions multiple application-specific regions and interacts with the individual application control layers to store switching information. The regions share the total available space. SDM consists of the following types of regions:

Exact-match region—The exact-match region consists of entries for multiple application regions such as IP adjacencies.

Longest-match region—Each longest-match region consists of multiple buckets or groups of
Layer 3 address entries organized in decreasing order by mask length. All entries within a bucket share the same mask value and key size. The buckets can change their size dynamically by borrowing address entries from neighboring buckets. Although the size of the whole application region is fixed, you can reconfigure it.

Weighted-exact-match region—The weighted-exact-match region consists of exact-match-entries with an assigned weight or priority. For example, with QoS, multiple exact match entries might exist, but some have priority over others. The weight is used to select one entry when multiple entries match.

Table 12-1 lists default partitioning for each application region.

Table 12-1 Default Partitioning by Application Region

Application Region
Lookup Type
Key Size
Default Size

IP Adjacency

Exact-match

64 bits

300 (shared)

IP Prefix

Longest-match

64 bits

300 (shared)

QoS Classifiers

Weighted exact-match

64 bits

300 (shared)

IP VRF Prefix

Longest prefix match

64 bits

300 (shared)

IP Multicast

Longest prefix match

64 bits

300 (shared)

MAC Addr

Longest prefix match

64 bits

8192

Access List

Weighted exact match

64 bits

300 (shared)


Configuring SDM

This section describes SDM region size and access control list (ACL) size configuration. The commands described in this section are unique to the switching software. Configuration changes take place immediately on the ML-100T-8 card.

Configuring SDM Regions

To configure SDM maximum size for each application region, perform the following procedure, beginning in global configuration mode:

 
Command
Purpose

Step 1 

ML_Series(config)# sdm size 
region-name number-of-entries

Configures the maximum number of entries for an SDM region.

Step 2 

ML_Series(config)# end

Exits to privileged EXEC mode.

An example of this is shown in Example 12-1.

Example 12-1 Limiting the IP-Prefix Region to 2K Entries

ML_Series # configure terminal
ML_Series(config)# sdm size ip-prefix 200
ML_Series(config)# end

Configuring Access Control List Size in TCAM

The default maximum size of the ACL is 300 64-bit entries. You can enter the sdm access-list command to change the maximum ACL database size, as shown in Table 12-2.

Table 12-2 Partitioning the TCAM Size for ACLs

Task
Command
sdm access-list number-entries

Sets the name of the application region for which you want to configure the size. You can enter the size as an absolute number of entries.


An example of this is shown in Example 12-2.

Example 12-2 Configuring Entries for the ACL Region in TCAM

ML_Series# configure terminal 
ML_Series(config)# sdm access-list 100
ML_Series(config)# end 

Monitoring and Verifying SDM

To display the number of available TCAM entries, enter the show sdm size command from global configuration mode:

ML_Series # show sdm size 
Active Switching Database Region Maximum Sizes : 
    IP Adjacency        : 300     64-bit entries
    IP Prefix           : 300     64-bit entries
    QoS Classifiers     : 300     64-bit entries
    IP VRF Prefix       : 300     64-bit entries
    IP Multicast        : 300     64-bit entries
    MAC Addr            : 8192    64-bit entries
    Access List         : 300     64-bit entries