Ping Monitor
The SiteScope Ping Monitor checks the availability of a host via the
network. Use this monitor to ensure that your connection to the Internet is
alive and well.
Each time the Ping Monitor runs, it returns a reading and a status
message and writes them in the monitoring log file. It also writes the
total time it takes to receive a response from the designated host in the
log file.
Usage Guidelines
The network can often be a Web traffic bottleneck, especially on
relatively slow wide area network connections. The Ping Monitor obtains two
of the most common measurements used to determine if your network
connection is congested: Round Trip Time and Loss Percentage. An increase
of either of these suggests that you are experiencing problems. In the
case of Loss Percentage, you want to see a 0% reading. A 100% reading
indicates your link is completely down. Some loss may happen very
occasionally, but if it becomes common, the network is either flaky (some
packets are being lost), or very busy and the router may be dropping the
Ping packets.
What to monitor
We suggest that you set up monitors that test your connection to the
Internet at several different points. For example, if you have a T1
connection to a network provider who in turn has a connection to the
backbone, you would want to set up a Ping Monitor to test each of those
connections. The first monitor would ping the router on your side of the
T1. The second would ping the router on your provider's side of the T1.
The third monitor would ping your provider's connection to the
backbone.
In addition to these monitors, it is also a good idea to have a
couple of other monitors ping other major network providers. These monitors
will not really tell you whether the other provider is having a problem,
but it will tell you if your network provider is having trouble reaching
them.
About scheduling this monitor
Because it will not cost you much performance wise, you can monitor
your own router as often as every two minutes or so. That way you will know
about any problems on your end as quickly as possible. The monitors that
watch your provider's connection to your line and to the backbone
should only be run every ten minutes or so. This will minimize traffic
while still providing you with sufficient coverage. Completing the Ping Monitor Form
To display the Ping Monitor Form, either click the Edit link for
an existing Ping Monitor listed in a monitor table, or click the add a
Monitor link on a group's detail page and click the
Add Ping Monitor link.
Complete the items on the Ping Monitor form as follows. When the
required items are complete, click the Add Monitor button.
- Host Name
-
Enter the IP address or the name of the host that you want to
monitor. For example, you could enter either 206.168.191.21 or
demo.thiscompany.com.
- Update every
-
Select how often the monitor should try to reach the host.
The default interval is to run or update the monitor once every 10 minutes.
Use the drop-down list to the right of the text box to specify another update
interval in increments of seconds, minutes, hours, or days. The update interval
must be 15 seconds or longer.
- Title
-
Enter a title text for this monitor. This text is displayed in the
group detail page, in report titles, and other places in the SiteScope
interface. If you do not enter a title text, SiteScope will
create a title based on the host, server, or URL being monitored.
Advanced Options
The Advanced Options section presents a number of ways to customize
monitor behavior and display. Use this section to customize error and warning
thresholds, disable the monitor, set monitor-to-monitor dependencies, customize
display options, and enter other monitor specific settings required for
special infrastructure environments. The options for this monitor type are
described below. Complete the entries as needed and click the Add
or Update button to save the settings.
- Disable
-
Check this box to temporarily disable this monitor and any
associated alerts. To enable the monitor again, clear the box.
- Time Out
-
This advanced option gives you the ability to customize the Ping
Monitor's time out threshold -- the time that should pass
before the ping times out. If you choose not to set it, SiteScope
uses a pre-set default of 5000 milliseconds. To change the
threshold, type the new value in the text box. The value must
be in milliseconds.
- Size
-
This advanced option gives you the ability to customize the size of
the ping packets sent. If you choose not to set it, SiteScope uses
a pre-set default of 64 bytes. To change the threshold, type the
new value in the text box. The value is in bytes.
- Verify Error
-
Check this box if you want SiteScope to automatically run this
monitor again if it detects an error. When an error is detected,
the monitor will immediately be scheduled to run again once.
Note: In order to change the run frequency of this
monitor when an error is detected, use the Update every (on
errors) option below.
Note: The status returned by the Verify Error run
of the monitor will replace the status of the originally scheduled
run that detected an error. This may cause the loss of important
performance data if the data from the verify run is different than
the initial error status.
Warning: Use of this option across many monitor instances
may result in significant monitoring delays in the case that
multiple monitors are rescheduled to verify errors at the same
time.
- Update Every (on error)
-
You use this option 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
-
By default, SiteScope 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. Click the Edit
schedule link to create or edit a monitor schedule.
For more information about working with monitor schedules,
see the section on Schedule
Preferences for Monitoring.
- Monitor Description
-
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
-
Enter an optional description for this monitor that will make it easier to
understand what the monitor does. For example, network traffic or
main server response time. This description will be displayed on
with each bar chart and graph in Management Reports and appended to
the tool-tip displayed when you pass the mouse cursor over the
status icon for this monitor on the monitor detail page.
- Depends On
-
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 on which this monitor is dependent. Select
None to remove any dependency.
- Depends Condition
-
If you choose to make the running of this monitor dependent on the
status of another monitor, select 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 on which it depends reports the
condition selected in this option.
- List Order
-
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
-
You use this option to customize the conditions under which the
Ping Monitor generates an error status message. Each time the Ping
Monitor runs, it pings the specified host and then returns a value
based on the average of all five pings. This helps to ensure
against false readings. By default the Ping Monitor reports an
error status any time it fails to reach a host after five pings.
You can change this to generate an error based on the average
length of the round trip times. To change the default choose either
% packets good or round trip time from the drop-down list. Next
choose a comparison symbol from the list. Use the comparison value
list to specify an error threshold.
Finally, enter the comparison value in the last text box
to create a complete equation, such as % packets good <= 90.
SiteScope's reported round trip time is actually the average
of the round trip times from all five pings executed each time the
monitor runs. Enter the lowest average round trip time (in
milliseconds) which should trigger an error status.
- Warning if
-
You use this option to customize the conditions under which the
Ping Monitor generates a warning status message. Each time the Ping
Monitor runs, it pings the specified host and then returns a value
based on the average of all five pings. By default the Ping Monitor
reports a warning status if it fails to reach a host on all five
pings.
To set the warning threshold, choose either % packets good or
round trip time from the drop-down list. Use the comparison
operator list to specify >= (greater than or equal to), != (not
equal to), or < (less than). Finally, enter the comparison value
in the last text box to create a complete equation, such as %
packets good <= 99.
SiteScope's reported round trip time is actually the average
of the round trip times from all five pings executed each time the
monitor runs. Enter the lowest average round trip time (in
milliseconds) which should trigger a warning status.
- Good if
-
You use this option to customize the conditions under which the
Ping Monitor generates a good status message. Each time the Ping
Monitor runs, it pings the specified host and then returns a value
based on the average of all five pings. This helps to ensure
against false readings. By default, the Ping Monitor returns a good
status if all five pings are successful. You may change this
default if you want.
To set the Good if threshold, choose either % packets good or
round trip time from the drop-down list. Next choose a comparison
symbol from the list. Use the comparison value list to specify an
good threshold.
Finally, enter the comparison value in the last text box
to create a complete equation, such as % packets good >= 90.
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