How Dhcp Client Is Implemented - Dell PowerEdge M IO Aggregator Command Reference Manual

Figure 7-6
and state transitions on a DHCP client interface when you release and renew a DHCP client.
Figure 7-6. DHCP Client: Debug Messages Logged during DHCP Client Release/Renew
FTOS# release dhcp interface managementethernet 0/0
May 27 15:55:22: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_EVT: Interface Ma 0/0 :
DHCP RELEASE CMD Received in state BOUND
May 27 15:55:22: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_PKT:
DHCP RELEASE sent in Interface Ma 0/0
May 27 15:55:22: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_EVT: Interface Ma 0/0 :
Transitioned to state STOPPED
May 27 15:55:22: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_EVT: Interface Ma 0/0 :
DHCP IP RELEASED CMD sent to FTOS in state STOPPED
FTOS# renew dhcp interface tengigabitethernet 0/1
FTOS#May 27 15:55:28: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_EVT: Interface Ma 0/0 :
DHCP RENEW CMD Received in state STOPPED
May 27 15:55:31: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_EVT: Interface Ma 0/0 :
Transitioned to state SELECTING
May 27 15:55:31: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_PKT:
DHCP DISCOVER sent in Interface Ma 0/0
May 27 15:55:31: %STKUNIT0-M:CP %DHCLIENT-5-DHCLIENT-LOG: DHCLIENT_DBG_PKT:
Received DHCPOFFER packet in Interface Ma 0/0 with Lease-Ip:10.16.134.250,
Mask:255.255.0.0,Server-Id:10.16.134.249

How DHCP Client is Implemented

The Aggregator is enabled by default to receive DHCP server-assigned dynamic IP addresses on an
interface. This setting persists after a switch reboot. If you enter the shutdown command on the interface,
DHCP transactions are stopped and the dynamically-acquired IP address is saved. Use the show interface
type slot/port command to display the dynamic IP address and DHCP as the mode of IP address
assignment. If you later enter the no shutdown command and the lease timer for the dynamic IP address
has expired, the IP address is unconfigured and the interface tries to acquire a new dynamic address from
DHCP server.
If you later enter the no shutdown command and the lease timer for the dynamic IP address has expired,
the IP address is released.
When you enter the release dhcp command, although the IP address that was dynamically-acquired from a
DHCP server is released from an interface, the ability to acquire a new DHCP server-assigned address
remains in the running configuration for the interface. To acquire a new IP address, enter either the renew
dhcp command at the EXEC privilege level or the ip address dhcp command at the interface
configuration level.
If you enter renew dhcp command on an interface already configured with a dynamic IP address, the lease
time of the dynamically acquired IP address is renewed.
Important: To verify the currently configured dynamic IP address on an interface, enter the show ip dhcp
lease command. The show running-configuration command output only displays ip address dhcp;
the currently assigned dynamic IP address is not displayed.
90 | Dynamic Host Configuration Protocol (DHCP)
shows an example of the packet- and event-level debug messages displayed for the packet transmissions