FTOS Configuration Guide for the C-Series - Force10 Networks

Bringing the Line Card Online
Bring the card back online using the online linecard command. The card will be reset. Use the show
linecard all command to verify the online status of the line card.
Buffer Tuning on C-Series and S-Series
Buffer tuning allows you to modify the way your switch allocates buffers from its available memory, and
helps prevent packet drops during a temporary burst of traffic.
Architecture Overview
Buffer tuning requires an understanding of:
• System architecture fundamentals, including the forwarding and/or switch fabric application-specific
integrated circuits (ASICs)
• Buffering fundamentals, including the difference between dedicated and dynamic buffers
• Default queueing and buffering behavior
Force10 recommends reviewing the following section before tuning the buffers.
The C-Series and S-Series ASICs implement the key functions of queuing, feature lookups, and
forwarding lookups in hardware. Forwarding Processor (FP) ASICs provide Ethernet MAC functions,
queueing and buffering, as well as store feature and forwarding tables for hardware-based lookup and
forwarding decisions. 1-GE 10-GE and 1-GE interfaces use different FPs. Switch Fabric (SFs) ASICs
provide some queuing while also providing the physical pathway through which frames are switched
between ports when the source and destination ports are attached to different FP ASICs.
Table 78 describes the type and number of ASICs per platform.
Table 78
Hardware FP CSF
48-port LC on C-Series 2 2
S50N, S50V 2 0
S25V, S25P, S25N 1 0
As can be seen at the FTOS CLI, buffer tuning can happen at three locations:
• FP Uplink (“fp-uplink”) – Output queues going from the 10-GE FP to SF high-speed internal
connection.
• Front-End Interfaces (“fp”) – Output queues going from the FP to the front-end PHY.
• CSF (“csf”) – Output queues going from the CSF.
FTOS Configuration Guide, version 7.7.1.0 711