Troubleshooting guide

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Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
OL-0800-14
Chapter 6 Troubleshooting the Cisco PGW 2200 Softswitch Platform
Resolving SS7 Network Related Problems
Verifying and Modifying RLM Timers
To change the values for these timers, change them on the Cisco PGW 2200 Softswitch and on the
associated media gateways. See the documentation for your media gateway for more information on
changing the RLM timers on the media gateway. To change the RLM timers on the Cisco PGW 2200
Softswitch, perform the following steps.
Note RLM keepalives are sent only when traffic has not been sent for some time; that is, when the Cisco PGW
2200 Softswitch receives a signaling message, the RLM keepalive timer is reset. The media gateway
sends RLM keepalives to the Cisco PGW 2200 Softswitch. If the RLM keepalive timer on the Cisco
PGW 2200 Softswitch expires, the system sets the IP link out-of-service. Increasing the RLM keepalive
timer values on both sides can ensure that the IP link is not reset during transient conditions in the IP
network, when the default values might be too stringent. However, if your system is in a continuous
service configuration, increasing the values of the RLM keepalive timers reduces the system’s ability to
quickly detect a link failure. Systems in a simplex configuration would not be affected.
Step 1 Verify the current settings of your RLM timers on the Cisco PGW 2200 Softswitch by logging in to the
standby Cisco PGW 2200 Softswitch, starting an MML session, and entering the
prov-rtrv:lnksetprop:name=“protocol_fam” command.
Where:
protocol_fam is the MML name for the associated protocol family.
For example, to retrieve the values of RLM timers for an ANSI signaling environment, enter the
prov-rtrv:lnksetprop:name=”ss7-ANSI” command.
The system returns a response like the following:
MGC-01 - Media Gateway Controller 2001-07-27 11:00:06
M RTRV
"session=active:lnksetprop"
/*
linkEchoRetry = 3
linkLatencyTest = 600
linkOpenWait = 30
linkRecovery = 120
linkSwitch = 50
linkUpRecoveredMin = 600
port = 3000
PropagateSvcMsgBlock = false
timerCmdAck = 10
timerLinkDownMin = 100
timerLinkEcho = 10
unstableLink = 10
*/
All the properties that are listed, except for port and PropagateSvcMsgBlock, are RLM timer properties.
Step 2 Start a provisioning session by using the procedure in the “Starting a Provisioning Session” section on
page 3-64.