Got it

Global address pool configuration

Latest reply: Dec 29, 2018 08:01:32 837 3 9 0 0

Hi, everyone! Today I’m going to introduce the global address pool configuration.

Dhcp enable

/* Enable DHCP Settings */

Ip pool abc



Configure the gateway.

[s1-ip-pool-abc]network mask

Configure an address pool. ( is a network segment, and is a broadcast address.)


The IP addresses that cannot be assigned are and

[s1-ip-pool-abc]lease day 2 hour 12 minute 0

Set the lease period to 2 days and 12 hours. (The default value is 1 day.)


Set the active DNS server to

Int g 0/0/0

[s1-GigabitEthernet0/0/0]ip address 24


[s1-GigabitEthernet0/0/0]dhcp select global

This command is used to enable the DHCP server that uses the global address pool on an interface.

Dis ip pool name abc

To query the information about the address pool abc, run the following command:

Dis ip pool name abc used

Query the usage of the abc address pool.

Note: Enable DHCP instead of manual write on the PC.

If you have any problems, please post them in our Community. We are happy to solve them for you!

  • x
  • convention:

Created Dec 29, 2018 06:10:16

The DHCP employs a connectionless service model, using the User Datagram Protocol (UDP). It is implemented with two UDP port numbers for its operations which are the same as for the bootstrap protocol (BOOTP). UDP port number 67 is the destination port of a server, and UDP port number 68 is used by the client.

DHCP operations fall into four phases: server discovery, IP lease offer, IP lease request, and IP lease acknowledgement. These stages are often abbreviated as DORA for discovery, offer, request, and acknowledgement.

The DHCP operation begins with clients broadcasting a request. If the client and server are on different subnets, a DHCP Helper or DHCP Relay Agent may be used. Clients requesting renewal of an existing lease may communicate directly via UDP unicast, since the client already has an established IP address at that point. Additionally, there is a BROADCAST flag (1 bit in 2 byte flags field, where all other bits are reserved and so are set to 0) the client can use to indicate in which way (broadcast or unicast) it can receive the DHCPOFFER: 0x8000 for broadcast, 0x0000 for unicast.[5] Usually, the DHCPOFFER is sent through unicast. For those hosts which cannot accept unicast packets before IP addresses are configured, this flag can be used to work around this issue.
View more
  • x
  • convention:

Created Dec 29, 2018 07:09:10

can we get the IP from the interface? the command is "dhcp select interface"
View more
  • x
  • convention:

Created Dec 29, 2018 08:01:32

When an enterprise has multiple addresses, it is best to use the global address pool.
View more
  • x
  • convention:


You need to log in to comment to the post Login | Register

Notice: To protect the legitimate rights and interests of you, the community, and third parties, do not release content that may bring legal risks to all parties, including but are not limited to the following:
  • Politically sensitive content
  • Content concerning pornography, gambling, and drug abuse
  • Content that may disclose or infringe upon others ' commercial secrets, intellectual properties, including trade marks, copyrights, and patents, and personal privacy
Do not share your account and password with others. All operations performed using your account will be regarded as your own actions and all consequences arising therefrom will be borne by you. For details, see " User Agreement."

My Followers

Login and enjoy all the member benefits


Are you sure to block this user?
Users on your blacklist cannot comment on your post,cannot mention you, cannot send you private messages.
Please bind your phone number to obtain invitation bonus.