Documentation forServer & Application Monitor

DHCP User Experience Monitor

The DHCP User Experience Monitor is a SAM component monitor included in several SAM application monitor templates to measures how long it takes to get a lease from a Dynamic Host Configuration Protocol (DHCP) server. It verifies that the DHCP server responds with an IP address, but neither confirms nor accepts the lease.

Note the following UDP port requirements for this component monitor:

  • For the DHCP request, the default value is 67 (IPv4) or 547 (IPv6).
  • For the DHCP response, the default value is 68 (IPv4) or 546 (IPv6).

Field descriptions

Description

A default description of the monitor. To override the default description, add to or replace existing text. Changes are automatically saved. The variable to access this field is ${UserDescription}.

Customize descriptions to specify what will be monitored so related alerts and notifications are more meaningful later.

Enable Component

Determines if a component is enabled. Disabling a component leaves it in the application as deactivated and does not influence application availability or status, as displayed in the Orion Web Console.

UDP Request Port

The UDP port used for the DHCP request. The default value for IPv4 is 67, for IPv6 is 547.

UDP Response Port

The UDP port used for the DHCP response. The default value for IPv4 is 68, for IPv6 is 546.

Sender Adapter IP Address (optional)

If the Orion server is configured for multiple network adapters, specify which adapter to use for the DHCP User Experience Monitor. Otherwise, the default (primary) network adapter is used.

DHCP Discovery Request Type

Select the DHCP Discovery Request Type:

  • Unicast: This is the default DHCP Discovery Request Type. The broadcast flag is not set, the ciaddr (Client IP Address) is set to the local address, and the giaddr (Relay Agent IP Address) is not set. The DHCP client sends a unicast DHCP DISCOVER to the DHCP server IP address and the UDP Request Port (defaults to 67). The DHCP server then sends a unicast DHCP Offer to the ciaddr address and the UDP Response Port (defaults to 68). This option can be used to monitor DHCP servers on the same subnet as the Orion server or on a different subnet.
  • Broadcast: The broadcast flag is set, the ciaddr (Client IP Address) is set to the local address, and the giaddr (Relay Agent IP Address) is not set. The DHCP client sends a unicast DHCP DISCOVER to the DHCP server IP address and the UDP Request Port (defaults to 67). The DHCP server then sends a broadcast DHCP Offer to the UDP Response Port (defaults to 68). This option can be used to monitor DHCP servers on the same subnet as the Orion server
  • Relay Agent: The broadcast flag is not set, the ciaddr (Client IP Address) is set to the local address, and the giaddr (Relay Agent IP Address) is set to the local address. The DHCP client sends a unicast DHCP DISCOVER to the DHCP server IP address and the UDP Request Port (defaults to 67). The DHCP server then sends a unicast DHCP Offer to the giaddr (Relay Agent IP Address) and the UDP Request Port (defaults to 67). This option can be used to monitor DHCP servers on the same subnet as the Orion server or on a different subnet.

    You can use the Broadcast or Relay Agent DHCP discovery request type to handle the issue with some DHCP servers (for example, an Internet Systems Consortium DHCP Server) that do not send a DHCP Offer back to the Orion server IP address. They send it to the newly leased IP address (the IP address being offered) instead. To handle this issue, set the DHCP Discovery Request Type to either Broadcast or Relay Agent.

Response Time Threshold

Set the warning and critical threshold conditions based on the response time. The response time is the time in milliseconds it takes SAM to determine that a component is not Down and to retrieve any statistical data.

User Notes

Add notes for easy reference. You can access this field by using the variable, ${UserNotes}.