Memory Configuration Options Obsoleted By Dynamic Memory; Basic Configuration Tasks; Enabling Bgp4 On The Router - Foundry Networks FESX Manual

Foundry Configuration Guide for the FESX, FSX, and FWSX
Table 21.2 lists the maximum total amount of system memory (DRAM) BGP4 can use. The maximum depends on
the total amount of system memory on the device.
Platform
FESX with 128 MB
FSX with Management 1 module with 256 MB
FSX with Management 2 module with 512 MB
The memory amounts listed in the table are for all BGP4 data, including routes received from neighbors, BGP
route advertisements (routes sent to neighbors), and BGP route attribute entries. The routes sent to and received
from neighbors use the most BGP4 memory. Generally, the actual limit to the number of neighbors, routes, or
route attribute entries the device can accommodate depends on how many routes the Layer 3 Switch sends to and
receives from the neighbors.
In some cases, where most of the neighbors do not send or receive a full BGP route table (about 80,000 routes),
the memory can support a larger number of BGP4 neighbors. However, if most of the BGP4 neighbors send or
receive full BGP route tables, the number of BGP neighbors the memory can support is less than in configurations
where the neighbors send smaller route tables.
As a guideline, Layer 3 Switches with a 512 MB Management 4 module can accommodate 150 – 200 neighbors,
with the assumption that the Layer 3 Switch receives about one million routes total from all neighbors and sends
about eight million routes total to neighbors. For each additional one million incoming routes, the capacity for
outgoing routes decreases by around two million.

Memory Configuration Options Obsoleted by Dynamic Memory

Devices that support dynamic BGP4 memory allocation do not require or even support static configuration of
memory for BGP4 neighbors, routes, or route attributes. Consequently, the following CLI commands and
equivalent Web management options are not supported on these devices:
• max-neighbors <num>
• max-routes <num>
• max-attribute-entries <num>
If you boot a device that has a startup-config file that contains these commands, the software ignores the
commands and uses dynamic memory allocation for BGP4. The first time you save the device's running
configuration (running-config) to the startup-config file, the commands are removed from the file.

Basic Configuration Tasks

The following sections describe how to perform the configuration tasks that are required to use BGP4 on the
Foundry Layer 3 Switch. You can modify many parameters in addition to the ones described in this section. See
"Optional Configuration Tasks" on page 21-21.

Enabling BGP4 on the Router

When you enable BGP4 on the router, BGP4 is automatically activated. To enable BGP4 on the router, enter the
following commands:
FESX424 Router> enable
FESX424 Router# configure terminal
FESX424 Router(config)# router bgp
BGP4: Please configure 'local-as' parameter in order to enable BGP4.
21 - 10
Table 21.2: Maximum Memory Usage
© Foundry Networks, Inc.
Maximum Memory BGP4
Can Use
30 MB
130 MB
400 MB
December 2005