References > Component Monitor Types > DHCP User Experience Monitor

DHCP User Experience Monitor

This component monitor measures how long it takes to get a lease from a DHCP server. The monitor verifies that the DHCP responds with an IP address, but neither confirms nor accepts the lease.

Statistic

This component monitor does not compute a statistic.

Field Descriptions

Description

This field provides a default description of the monitor. You have the ability to override the default description by adding to or replacing the text, which is automatically saved. The variable to access this field is ${UserDescription}.

Enable Component

Determines whether the component is enabled. Disabling the component leaves it in the application in a deactivated state not influencing either SolarWinds SAM application availability or status.

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)

For SolarWinds servers with multiple network adapters configuration, this field specifies which of the multiple network adapters is used for the DHCP User Experience monitor. If this setting is not specified, the default (primary) network adapter is used.

This setting does not affect SolarWinds servers with only one network adapter.

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 SolarWinds SAM 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 SolarWinds SAM 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 SolarWinds SAM 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 Internet Systems Consortium DHCP Server) that do not send a DHCP Offer back to the SolarWinds SAM 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

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

User Notes

This field allows you to add notes for easy reference. You can access this field by using the variable, ${UserNotes}.