SiteScope User's Guide

Network Monitor

The SiteScope Network Monitor provides an easy way for you to track network statistics for your server. Information provided by the network monitor can help you track down performance problems related to network interfaces on your servers.

Each time the Network Monitor runs, it returns a reading and a status message and writes them in the ~SiteScope/logs/SiteScope.log file.

Usage Guidelines

Why should I use this monitor?

Web server performance is dictated largely by the network interface. The actual number of bytes being passed in and out of your server as well as the number of packets in error are all critical measures of a server's performance and are tracked by the Network Monitor. In addition, active connections are tracked.

How often should I schedule this monitor to run?

In most environments, scheduling the Network Monitor to run every 10 minutes should be sufficient. SiteScope can notify you if network performance begins to slow, and you will have enough data points to create meaningful reports for comparison and trend analysis.

What are common problems and how do I fix them?

Packet Errors measure the number of packets that failed to reach the destination IP address. This can indicate a faulty network interface or media. If the problem shows up on several servers that are topologically close, it is likely the media. If this condition occurs on only one isolated server, you can suspect the interface.

Throughput indicators let you know how fully utilized your network interface is. For instance, if you are running on a conventional ethernet interface and you see numbers approaching 10 megabits / sec., the interface is nearly saturated.

Connections is the count of open ports on your network interface. This measure should settle at some some predictable level. Continuous climbing of the connection count indicates an error condition or run-away condition that will eventually slow the server due to resource constraints.

Status

The reading is the current value of the monitor, such as 40% saturated. The status is logged as either OK, warning, or error. A warning status is returned if the bytes out per second is more than 80% full. Full is defined as a fully saturated standard ethernet bandwidth or 10 megabits / sec. An error status is returned if bytes out per second is more than 90% saturation.

Completing the Network Monitor Form

To display the Network Monitor Form, either click the name of an existing Network Monitor in a monitor table, or click the Add a new Monitor to this Group link on a group's detail page and choose the Add Network Monitor link.

Complete the items on the Network Monitor Form as follows. When the required items are complete, click the Update Monitor button.

Update every: Enter how frequently the monitor should check this interface. The drop-down list to the right of the text box lets you specify time increments of seconds, minutes, hours, or days. You must specify a time increment of at least 15 seconds.
Title (Optional): Enter a name for this monitor. This name appears in the Name text box on the monitor table when you open the group's detail page. If you don't enter a name, a default name will be created.

Advanced Options

The advanced options give you the ability to customize error and warning condition thresholds. If you choose not to set them, SiteScope uses pre-set defaults if available. If a default is not available, SiteScope cannot utilize the condition.

Disable

Check this box to temporarily disable this monitor and any associated alerts. To enable the monitor again, clear the box.

Verify Error

Check this box if you want SiteScope to automatically run this monitor again when it detects an error.

Update Every (on error)

This options allows you to set a new monitoring interval for monitors that have registered an error condition. For example, you may want SiteScope to monitor this item every 10 minutes normally, but as often as every 2 minutes if an error has been detected. Note that this increased scheduling will also affect the number of alerts generated by this monitor.

Schedule (Optional)

By default, SiteScope's monitors are enabled every day of the week. You may, however, schedule your monitors to run only on certain days or on a fixed schedule. Choose the Edit schedule link to create or edit a monitor schedule. For information about creating schedules, read these instructions.

Monitor Description (Optional)

Enter additional information about this monitor. The Monitor Description can include HTML tags such as the <BR> <HR>, and <B> tags to control display format and style. The description will appear on the Monitor Detail page.

Report Description (Optional)

Enter a description for this monitor that will make it easier to understand what this monitor does. The description will appear on Management Reports and on the info list for a monitor.

Depends On (Optional)

To make the running of this monitor dependent on the status of another monitor or monitor group, use the drop-down list to select the monitor or group on which this monitor is dependent. Select None to remove any dependency.

Depends Condition (Optional)

If you choose to make the running of this monitor dependent on the status of another monitor, choose the status condition that the other monitor or monitor group should have in order for the current monitor to run normally. The current monitor will be run normally as long as the monitor or group on which it depends reports the condition selected in this option.

List Order (Optional)

By default, new monitors are listed last on the Monitor Detail page. You may use this drop-down list to choose a different placement for this monitor.

Error if

Set the Error threshold for this monitor. By default SiteScope reports an error condition if any packet errors occur. You can change this to be dependent upon packet errors per second, the number of active connections, bytes per second received, or bytes per second sent. Choose the option you want from the drop-down list, select a comparison value symbol, and enter the threshold number in the text entry box. You must enter a whole number.

For example, if you want SiteScope to report an error condition if your packed error count exceeds 5 errors per second, you need to choose errorsPerSecond >= from the pull-down menus and then enter 5 in the text entry box.

Warning if

Set the warning threshold for this monitor. By default SiteScope reports a warning condition if your bytes out per second is more than 50000. You can change this to be dependent upon packet errors per second, the number of active connections, bytes per second received, or bytes per second sent.

For example, if you want to change the warning threshold to 10000, choose outBytesPerSecond > from the drop-down lists and then enter 10000 in the text entry box.

Good if

By default SiteScope assumes a good status. You can change this to be dependent upon packet errors per second, the number of active connections, bytes per second received, or bytes per second sent.