Cisco Cisco IOS Software Release 12.4(2)XB6
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Release Notes for Cisco GGSN Release 10.x on the Cisco SAMI, Cisco IOS Software Release 12.4(24)YE Releases
Limitations, Restrictions, and Important Notes
Limitations, Restrictions, and Important Notes
When configuring Cisco GGSN Release 10.x, note the following:
•
The Cisco GGSN Release 8.0 and later does not support the Cisco Express Forwarding (CEF)
neighbor resolution optimization feature, which is enabled by default.
neighbor resolution optimization feature, which is enabled by default.
Therefore, to avoid the possibility of incomplete adjacency on VLAN interfaces for the redirected
destination IP address and an impact to the upstream traffic flow for PDP sessions, ensure that you
configure the no ip cef optimize neighbor resolution command.
destination IP address and an impact to the upstream traffic flow for PDP sessions, ensure that you
configure the no ip cef optimize neighbor resolution command.
•
To avoid issues with high CPU usage, we recommend the following configurations:
–
To reduce the CPU usage during bootup, disable logging to the console terminal by configuring
the no logging console global configuration command.
the no logging console global configuration command.
–
To ensure that the HSRP interface does not declare itself active until it is ready to process a
peer’s Hello packets, configure the delay period before the initialization of HSRP groups with
the standby delay minimum 100 reload 100 interface configuration command under the
HRSP interface.
peer’s Hello packets, configure the delay period before the initialization of HSRP groups with
the standby delay minimum 100 reload 100 interface configuration command under the
HRSP interface.
–
To minimize issues with high CPU usage for additional reasons, such as periods of high PPP
PDP processing (creating and deleting), disable the notification of interface data link status
changes on all virtual template interfaces of the GGSN using the no logging event link-status
interface configuration command.
PDP processing (creating and deleting), disable the notification of interface data link status
changes on all virtual template interfaces of the GGSN using the no logging event link-status
interface configuration command.
!
interface Virtual-Template1
description GGSN-VT
ip unnumbered Loopback0
encapsulation gtp
no logging event link-status
gprs access-point-list gprs
end
•
The number of PDP contexts supported on a GGSN is dependent on the memory and platform in use
and the GGSN configuration (for example, whether or not a method of Point-to-Point Protocol [PPP]
is configured to forward packets beyond the terminal equipment and mobile termination, if Dynamic
Feedback Protocol [DFP] is being used or the memory protection feature is enabled, and the rate of
PDP context creation that is supported).
and the GGSN configuration (for example, whether or not a method of Point-to-Point Protocol [PPP]
is configured to forward packets beyond the terminal equipment and mobile termination, if Dynamic
Feedback Protocol [DFP] is being used or the memory protection feature is enabled, and the rate of
PDP context creation that is supported).
Note
DFP weighs PPP PDPs against IP PDPs with one PPP PDP equal to eight IP PDPs. One IPv6
PDP equals 8 IPv4 PDPs.
PDP equals 8 IPv4 PDPs.