The Option 55 field in DHCP Request messages is used to set the request option list. DHCP clients use this option to specify network configuration parameters that need to be obtained from the DHCP server. You can run the dhcp client request option-list exclude command to set a list of default options that are excluded from the Option 55 field or run the dhcp client request option-list command to set a list of other options that the Option 55 field carries besides the default options based on network requirements. The other options include option 4, 7, 17, 42, 43, 66, 67, 120, and 129.
For option meanings, see Introduction to DHCP Messages.
system-view
interface interface-type interface-number
dhcp client request option-list exclude option-code &<1-8>
By default, the device does not configure the option to be excluded from the DHCP client request list.
dhcp client request option-list option-code &<1-9>
By default, the Option 55 field in DHCP Request packets carries only default request options.