Cisco Cisco IOS Software Release 12.2(4)B

Release Notes for Cisco 6400 for Cisco IOS Release 12.2(4)B3

OL-1650-03

Important Notes

Note

In most NRP-2 configurations, 256 MB DRAM is adequate for up to 6500 (PPPoE) sessions. More
sessions require 512 MB DRAM.

NRP-2SV Scalability Tuning Parameters

Following are scalability tuning parameter values used during testing for 6000 PPPoA sessions and 2000
L2TP tunnels. These parameters prevent known issue CSCdu86416 from happening.

interface Virtual-Template1
keepalive 200
ppp timeout retry 25
ppp timeout authentication 20

vpdn-group 1
l2tp tunnel hello 150
l2tp tunnel receive-window 500
l2tp tunnel nosession-timeout 20
l2tp tunnel retransmit retries 12
l2tp tunnel retransmit timeout min 4
l2tp tunnel retransmit timeout max 6

Following is the hold-queue CLI used during testing.

interface ATM0/0/0
no ip address
load-interval 30
atm vc-per-vp 2048
no atm ilmi-keepalive
hold-queue 4096 in
hold-queue 4096 out
end

Tip

With PPPoA over L2TP network architecture, a few PPP sessions may not have IP addresses
allocated during system reboot or interface flapping. If you encounter this problem, configure ppp
ncp timeout in the template on LNS as shown here:

interface Virtual-Template1
ppp timeout ncp 60

It is important to note a potential negative impact on PPPoX termination scenarios:

The default is no time-out at all. Configuring ppp timeout ncp 60 tells the router if NCP cannot be
established within 60 seconds to tear down LCP and start all over again.

Note that you should only configure ppp timeout ncp 60 if you encounter the IP address allocation
problem described here. Do not configure the timeout indiscriminately or to any local termination
PPPoA/PPPoE deployment.

Note

In most NRP-2 configurations, 256 MB DRAM is adequate for up to 6500 (PPPoE) sessions. More
sessions require 512 MB DRAM.