Cisco Cisco Packet Data Gateway (PDG)
Evolved Packet Data Gateway Overview
Features and Functionality ▀
ePDG Administration Guide, StarOS Release 17 ▄
33
Option
Description
system-cpu-utilization
percent
The average percent utilization for all PSC2 CPUs available to the system as
measured in 10-second intervals.
measured in 10-second intervals.
percent
can be an integer from 0 through 100.
Default: 80
system-memory-utilization
percent
The average percent utilization of all CPU memory available to the system as
measured in 10-second intervals.
measured in 10-second intervals.
percent
can be an integer from 0 through 100.
Default: 80
Important:
For more information on congestion control, including configuration instructions, see the System
Administration Guide. For more information on the
congestion-control threshold
command, see the
eHRPD/LTE Command Line Interface Reference.
Session Recovery Support
Session recovery provides seamless failover and reconstruction of subscriber session information in the event of a
hardware or software fault within the system, preventing a fully connected user session from being disconnected. The
ePDG supports session recovery for IPv4, IPv6, and IPv4/v6 sessions and ensures that data and control planes are re-
established as they were before the recovery procedure.
hardware or software fault within the system, preventing a fully connected user session from being disconnected. The
ePDG supports session recovery for IPv4, IPv6, and IPv4/v6 sessions and ensures that data and control planes are re-
established as they were before the recovery procedure.
When session recovery occurs, the system reconstructs the following subscriber information:
Data and control state information required to maintain correct call behavior, including DNS, P-GW, and P-
CSCF addresses.
Subscriber data statistics that are required to ensure that accounting information is maintained.
A best-effort attempt to recover various timer values, such as call duration, absolute time, and others.
Note that for the recovered sessions, the ePDG recreates counters only and not statistics.
Session recovery is also useful for in-service software patch upgrade activities. If session recovery is enabled during the
software patch upgrade, it helps to preserve existing sessions on the active hardware during the upgrade process.
software patch upgrade, it helps to preserve existing sessions on the active hardware during the upgrade process.
Important:
For more information on session recovery support, see the System Administration Guide.
ICSR Support
The ePDG supports ICSR with fault detection and automatic switch over. Subscriber session details for all ePDG
interfaces are replicated in standby, In case of a switchover, the new chassis processes all subsequent control and data
traffic for the subscriber session.
interfaces are replicated in standby, In case of a switchover, the new chassis processes all subsequent control and data
traffic for the subscriber session.
The SWu, SWm and S2b interface are not impacted by the switchovers.
Important:
For more information on ICSR, see the System Administration Guide.