- DHCP Option Numbers
- NTP Server via DHCP Server - Cisco Community
- The TCP/IP Guide - Summary Of DHCP Options / BOOTP Vendor
- Dynamic Host Configuration Protocol (DHCP) and Bootstrap
Option 66 Identifies the vendor of the hardware on which the client is hosted. Option 66 is equivalent to the vendor-id sub-option of DHCP option 87.
DHCP Option Numbers
In the window, check one or more options and specify its value in the Data entry box. For example, the following figure shows the addition of the Router.
NTP Server via DHCP Server - Cisco Community
DHCPv6 provides several options that can be used to insert information into the DHCPv6 request packets that are relayed to a server from a client. These options are equivalent to the sub-options of DHCP option 87.
The TCP/IP Guide - Summary Of DHCP Options / BOOTP Vendor
Options containing NVT ASCII data SHOULD NOT include a trailing NULL. The receiver of such options MUST be prepared to delete trailing NULLs if they exist. The receiver MUST NOT require that a trailing NULL be included in the data. In the case of some variable length options, the length field is a constant but must still be specified.
Dynamic Host Configuration Protocol (DHCP) and Bootstrap
If the switching device, the DHCP clients, and the DHCP server are all on the same VLAN or bridge domain, the switching device forwards the requests from the clients on untrusted access interfaces to the server on a trusted interface. See Figure 6.
From the same DHCP console, expand a Scope and go to the Scope Options folder where you will find all the options you have set for this Scope.
Configuring DHCP Options at the Server level means that all DHCP clients will have the same options regardless of the Scope they belong to. Correspondingly, by adjusting them to the Scope level, then we can have different options for each Scope separately. How you handle it is purely a matter of your infrastructure needs.
If option 87 is enabled on a VLAN or bridge domain, the following sequence of events occurs when a DHCP client sends a DHCP request:
DHCP options have the same format as the BOOTP 'vendor extensions'. Options may be fixed length or variable length. All options begin with a tag byte, which uniquely identifies the option. Fixed length options without data consist of only a tag byte. The value of the length byte does not include the tag and length fields.
To use the DHCP option 87 feature, you must ensure that the DHCP server is configured to accept option 87. If the DHCP server is not configured to accept option 87, then when it receives requests containing option 87 information, it does not use the information for setting parameters and it does not echo the information in its response message.