Use this Knowledge Script to monitor the percentage of DHCP address leases that are being used. This script raises an event if the percentage of addresses used exceeds the threshold you set or the number of available addresses falls below the threshold you set. This script can monitor addresses for each DHCP scope individually or for the entire DHCP server.
The concept of a DHCP address lease is one in which a client computer does not retain a permanent DHCP address. With a DHCP lease, a client computer communicates with a DHCP server on reboot to begin or confirm the lease of an address.
This script requires the Microsoft SNMP service to be running.
DHCP service object
The default interval for this script is Every 30 minutes.
Set the following parameters as needed:
|
Parameter |
How to Set It |
|---|---|
|
Event for total address usage? |
Set to y to raise events when the percentage of addresses used or the number of available addresses exceeds the threshold for the entire DHCP server. The default is y. |
|
Event for scope address usage? |
Set to y to raise events when the percentage of addresses used or the number of available addresses exceeds the appropriate threshold for any DHCP scope. The default is y. |
|
Collect data for total address usage? |
Set to y to collect data for charts and reports. If enabled, data collection returns the total number of addresses in use. The default is n. |
|
Collect data for scope address usage? |
Set to y to collect data for charts and reports. If enabled, data collection returns the number of addresses in use in a DHCP scope. The default is n. |
|
Maximum threshold for the percentage of total addresses in use |
Specify the maximum percentage of addresses that can be in use at one time for the entire DHCP server (total addresses available) before an event is raised. The default is 95%. |
|
Maximum threshold for percentage of addresses in use in a scope |
Specify the maximum percentage of addresses that can be in use in a DHCP scope before an event is raised. The default is 80%. A DHCP scope is the range of IP addresses that the DHCP server can assign to clients that are on one subnet. |
|
Minimum threshold for total number of addresses available |
Specify the minimum number of addresses that must be available for the DHCP server to prevent an event from being raised. The default is 10. |
|
Minimum threshold for number of addresses available in a scope |
Specify the minimum number of addresses that must be available in a DHCP scope to prevent an event from being raised. The default is 5. |
|
Event severity level for total usage high or availability low |
Set the event severity level, from 1 to 40, to indicate the importance of an event in which the percentage of addresses in use exceeds the threshold or the number of available addresses falls below the threshold. The default is 10 (red event indicator). |
|
Event severity level for scope usage high or availability low |
Set the event severity level, from 1 to 40, to indicate the importance of an event in which the percentage of addresses in use in a scope exceeds the threshold or the number of available addresses in a scope falls below the threshold. The default is 15 (yellow event indicator). |
|
Community |
Specify the SNMP community string. The default is either the community name entered in AppManager Security Manager or public if no community name has been entered. The default is public. |