Manage DHCP services

DHCP provides a framework to assign configuration information to hosts, including IP addresses, gateway addresses, and DNS server addresses.

DHCP provides efficient IP address assignment services for medium networks or large networks that contain more than 100 VMs. Configurations on VMs are simplified as VMs automatically obtain IP addresses and configurations through DHCP.

Operators can configure multiple DHCP services on a virtual switch. Each DHCP service provides IP address assignment for VMs in a specific VLAN. A VM can use a DHCP service on a virtual switch when it is assigned the virtual switch and the VLAN ID in the DHCP service.

Operators can add, edit, and delete DHCP services for a virtual switch.

Restrictions and guidelines

• The DHCP server of a DHCP service uses the start IP address of the IP address pool of the DHCP service.

• The IP address pools of DHCP services cannot overlap.

• After you delete a DHCP service from a virtual switch, VMs that have been assigned IP addresses lose the IP addresses after a period of time, and VMs newly join the virtual switch cannot obtain IP addresses.

Add a DHCP service

1. On the top navigation bar, click Hosts.

2. Select the target host, and then click the vSwitches tab.

3. Click the Advanced icon  for a virtual switch.

4. Click the DHCP Services tab.

5. Click Add.

6. Configure the DHCP service parameters as described in "Parameters."

7. Click OK.

Edit a DHCP service

1. On the top navigation bar, click Hosts.

2. Select the target host, and then click the vSwitches tab.

3. Click the Advanced icon  for a virtual switch.

4. Click the DHCP Services tab.

5. Click the Edit icon  for a DHCP service.

6. Edit the DHCP service parameters as described in "Parameters."

7. Click OK.

Delete DHCP services

1. On the top navigation bar, click Hosts.

2. Select the target host, and then click the vSwitches tab.

3. Click the Advanced icon  for a virtual switch.

4. Click the DHCP Services tab.

5. Click the Edit icon  for a DHCP service.

6. In the dialog box that opens, click OK.

Parameters

• VLAN ID: Enter the VLAN ID of the DHCP service. On a virtual switch, the VLAN ID of a DHCP service must be unique. A VM can automatically obtain an IP address after it is configured with a VLAN ID and a virtual switch.

• Start Address: Enter the start IP address of the IP address pool. The DHCP server uses this IP address. The IP address pools cannot contain multicast or loopback addresses. The start IP address cannot be 127.*.*.*.

• End Address: Enter the end IP address of the IP address pool. The end address must be higher than the start address. An IP address pool can contain a maximum of 5000 IP addresses. The IP address pools cannot contain multicast or loopback addresses. The end IP address cannot be 127.*.*.*.

• Subnet Mask: Enter a subnet mask. Make sure the start address and the end address are in the same network segment, and the network segments of two IP address pools do not overlap.

• Gateway Address: Enter the gateway address of the DHCP service.

• DNS Address: Enter the IP address of the DNS server.

• Lease: Specify the lease duration of the DHCP service. If you do not specify this parameter, leases are unlimited.

• Address Usage: Number of assigned IP addresses and number of available IP addresses. Each box represents an IP address. A green box represents an assigned IP address, and a grey box represents an available IP address. You can hover the cursor over a box to view detailed information about the IP address.