Troubleshooting guide

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Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
OL-0800-14
Chapter 3 Cisco PGW 2200 Softswitch Platform Operations
Regular Operations
• GLBL.ablack—Contains global screening data for A-number black lists. Introduced in Release
9.4(1).
• GLBLbwhite—Contains global screening data for B-number white lists. Introduced in Release
9.4(1).
• GLBLbblack—Contains global screening data for B-number black lists. Introduced in Release
9.4(1).
For example, to export all of the provisioning data into files that are stored in the /opt/CiscoMGC/etc/
cust_specific saved_config directory, enter the prov-exp:all:dirname=“saved_config” command:
Managing Automatic Congestion Control
The Cisco PGW 2200 Softswitch supports Automatic Congestion Control (ACC). ACC dynamically
regulates incoming traffic on the Cisco PGW 2200 Softswitch to levels that can be processed effectively.
The regulation requires rejecting a percentage of new calls when the Cisco PGW 2200 Softswitch is
congested. ACC increases the throughput of completed calls through the telephone network during
periods of overload.
ACC provides three major functions:
• Rejection of calls to prevent internal congestion—When the Cisco PGW 2200 Softswitch is
congested, it rejects a user-defined percentage of calls (depending on internal overload level) and
sends an ISUP release message to the adjacent signaling point. That ISUP release message has a
clear cause of Switch Equipment Congestion and contains an Automatic Congestion Level (ACL)
value that indicates the overload level of the Cisco PGW 2200 Softswitch. For a call that is in
progress when overload occurs and the call clears normally, the ISUP release message has a clear
cause of Normal Call Clearing and an ACL value that is associated with the current overload level
of the Cisco PGW 2200 Softswitch.
• Reception and response to congested status—When an adjacent signaling point is congested, the
Cisco PGW 2200 Softswitch can reduce the amount of traffic that is offered by rerouting calls or by
rejecting a percentage of the calls. This response to congestion is referred to as outgoing load control
(OLC).
• Detection and transmission of congested status—The Cisco PGW 2200 Softswitch can indicate its
current level of congestion to adjacent signaling points using SS7 ISUP. Detection of congestion is
based on dynamic measurements such as CPU occupancy, size of queues and buffers, or amounts of
other resources that are needed for call processing. This detection of congestion is referred to as
incoming load control (ILC).
ACC is described in the following sections:
• Managing Call Rejection Percentages, page 3-77
• Managing Outgoing Load Control, page 3-80
• Managing Incoming Load Control, page 3-91
Managing Call Rejection Percentages
ACC enables the Cisco PGW 2200 Softswitch to manage its internal congestion level by rejecting calls.
When call volume causes the Cisco PGW 2200 Softswitch to reach one of its machine congestion levels
(MCLs), the system can send ACL indications to the adjacent signaling points and release a percentage
of calls that you define.
The valid values for MCL are shown in Table 3-14.