Cisco Systems OL-11291-01 manual Ftp

Appendix A IPM FAQs and Troubleshooting Tips

IPM FAQs

Q.How frequently can network performance measurements be taken?

A.SA Agent generates several measurements per hour, then IPM polls the router once per hour and collects summarized statistics for that period. You can set the sampling interval for SA Agent for as often as every 10 seconds, but for optimal performance, we recommend a sample interval of at least 60 seconds (1 minute). This is the default value.

You can view up-to-date real-time statistics in the Real Time Statistics window as SA Agent collects the data from the collector. However, IPM does not store the real-time data in the IPM database. IPM stores only the hourly summarized data in the IPM database.

Q.When IPM collects the data from the SA Agent using SNMP, is this data averaged or summarized in any way?

A.The data is summarized and averaged in a variety of ways. IPM displays the data in the Historical Statistics window in hourly, daily, weekly, and monthly increments. IPM also displays average, minimum, and maximum calculations of the data over the monitoring period. IPM also provides an automatic aging facility for summarizing and aging older data.

Q.What data collectors are available in IPM 2.6?

A.IPM Release 2.6 provides support for the following types of operations:

•DHCP Echo

•DLSw Echo

•DNS Echo

•Enhanced UDP with Jitter Monitoring

•HTTP Connect

•ICMP Echo

•ICMP Path Echo

•SNA Echo

•TCP Connect

•UDP Echo

•FTP

This release also provides support for Loose Source Routing and Quality of Service.

Q.For TCP Connect operations, what port numbers does IPM support?

A.You can make a TCP connection to any port number, well known or otherwise, on any IP host, Cisco or non-Cisco, as long as someone is listening on that port on the target.

If you specify a SA Agent device as a target, make sure you configured it as a Cisco SAA Responder target on the Target Configuration window. If you mistakenly configured it as an IP target, and you specify a Target Port that is not well known (that is, if you specify a port number greater than 1024), IPM considers the target an IP device rather than an SA Agent device and does not enable the SA Agent Control protocol. As a result, the collector cannot connect to the target and no data is collected.

User Guide for Internetwork Performance Monitor

OL-11291-01 A-7