для Cisco Cisco IOS Software Release 12.4(2)XB6

Syslog is a method to collect messages from devices to a server running a syslog daemon. Logging to a 
central syslog server helps in aggregation of logs and alerts. Cisco devices can send their log messages 
to a UNIX-style SYSLOG service that simply accepts messages and stores them in files or prints them 
according to a simple configuration file. This form of logging is very useful for Cisco devices because 
it can provide protected long-term storage for logs. This is useful both in routine troubleshooting and in 
incident handling.

The Cisco call agent can capture voice quality statistics sent from MGCP-controlled media gateways and 
can propagate the statistics into call detail records (CDRs) at the end of each call. Cisco gateways send 
voice quality statistics to the Cisco call agent.

Most voice quality statistics are available from the DSP and are controlled with RTP Control Protocol 
(RTCP) report interval statistics polling. The mean and maximum values are calculated by Cisco IOS 
software-based polling. This results in an additional CPU load for each call, which can be controlled by 
the configured polling interval using the ip rtcp report interval commands.

The playout delay, playout error, and DSP receive and transmit statistics are automatically polled 
periodically. You can add polling for the voice quality statistics, level, and error parameters. For logging 
the voice quality statistics using Syslog, the existing VoIP gateway accounting has been extended. Use 
the ip rtcp report interval command reference for more information about statistics polling. 

DSP voice quality metrics can be used to troubleshoot the following problems:

For additional DSP troubleshooting information, see the

 

section in the 

.

Troubleshoot one-way audio problems by using the following DSP voice quality metrics:

Use the tranmission (DSP/TX) and receive (DSP/RX) statistics to determine if packets are only 
moving in one direction. 

Use the level (DSP/LE) statistics to check incoming and outgoing activity.

Use endpoint configuration (DSP/CE) statistics to determine if there is a codec mismatch.

Troubleshoot echo problems by using the following DSP voice quality metrics:

Check the delay (DSP/DL) and R-factor (DSP/RF) statistics. You might find perceptible delay 
between when the originating signal is transmitted and when the echo returns. In most telephones, 
sidetone helps mask some of the echo. Echos must be delayed by at least 20 milliseconds to be 
perceived.