DHCP (PI_DHCP)

Function

The DHCP (PI_DHCP) record stores information about DHCP service response time. This is a multi-instance record.

Default and changeable values

ItemDefault valueChangeable
Collection Interval360Y
Collection Offset0Y
LogNoY
LOGIF(Blank)Y

ODBC key fields

PI_DHCP_MSR_COND_ID

Lifetime

None

Record size

Fields

View name
(Manager name)
DescriptionSummary ruleFormatDeltaData source
Address Assignment Time
(ADDR_ASSIGN_TIME)
Address presentation time (seconds) ((2) in Figure 9-1)AVGdoubleNoProbe Daemon
Address Reservation Time
(ADDR_RESERV_TIME)
Address acquisition time (seconds) ((3) in Figure 9-1)AVGdoubleNoProbe Daemon
Total Amount of Data
(TOTAL_DATA_SIZE)
Total amount of data transferred between the DHCP probe and the monitored server on UDP (bytes)AVGdoubleNoProbe Daemon
Total Response Time
(TOTAL_RESP_TIME)
Total response time (seconds) ((1) in Figure 9-1)AVGdoubleNoProbe Daemon

The following figure shows the DHCP sequence.

Figure 9-1 DHCP sequence

[Figure]

DHCP operating environment and notes

A DHCP probe searches for the measurement-target DHCP server and measures the time required for dynamically acquiring the IP address.

The following describes and provides notes on a DHCP operating environment.

Acquisition of IP address

The DHCP probe broadcasts an address presentation request and receives an address presentation from the DHCP server. To accept the presented IP address, address acquisition as shown in Figure 9-1 is performed. If the presented IP address is not to be accepted, address acquisition is not performed.

The address presentation request, address acquisition request, and their responses are all sent by broadcasting.

Release of IP address

If IP address acquisition is successful, address release as shown in Figure 9-1 is performed. If the presented IP address is not to be accepted, or if acquisition fails, address release is not performed. The time required for this address release is not included in the total response time.

Port number of the probe

Specify the port number of the DHCP client that has been defined at the monitoring-target DHCP server. Do not define more than one measurement item with the same probe port number.

RFC compliance