DHCP WAN request options

Installing and Using OpenWrt
1

In f.e. OpnSense of PfSense it is possible to configure DHCP request options for the WAN side.
In OpenWrt I can’t find where to do that, is it not possible?

For my ISP I would like to configure classles-routes f.e. which is option 121 to be sent.

2

Edit the WAN interface under Network - Interfaces in LuCI.

See the wiki for manually setting the classless route option.

2 Likes
3

I know, but where can I put request options? There is no field for it..
On the given page I can see all those options, but in Luci I can’t find them under the advanced tab of my WAN interface?

4

Option 121 is enabled by default for DHCP, so if you need to disable it, you would need to use uci commands.

1 Like
5

I see it now indeed.
No, I need it enabled and I see it’s default.

I am now working on my config using SSH to put in the request options. I will (when finished) post it to check if it is correct.

I need to request option 55 which includes option (1,3,28 and 121)

This is what I got now:

config interface 'wan_iptv'
option proto 'dhcp'
option device 'eth1.4'
option vendorid 'IPTV_RG'
option defaultroute '0'
option peerdns '0'
option delegate '0'
option hostname '*'
option classlessroute '1'
option reqopts 'subnet-mask routers broadcast-address'

or do I need to fill the reqopts like this:

option reqopts '55'

or like this

option reqopts '1 3 28'
6

It is requested by default, so if something isn't working for you as expected, you should look elsewhere.

0.0.0.0.68 > 255.255.255.255.67: [udp sum ok] BOOTP/DHCP, Request from 90:9a:4a:96:c2:7c, length 300, xid 0x774ed201, Flags [Broadcast] (0x8000)
          Client-Ethernet-Address 90:9a:4a:96:c2:7c
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message (53), length 1: Discover
            MSZ (57), length 2: 576
            Parameter-Request (55), length 8:
              Subnet-Mask (1), Default-Gateway (3), Domain-Name-Server (6), Hostname (12)
              Domain-Name (15), BR (28), NTP (42), Classless-Static-Route (121)
            ...
1 Like
7

Thanks!

No everything is working fine I was just looking in the documentation with instructions of my ISP for setting things up and saw these settings.

Didn’t know option 50 and 121 were default, but that’s why it was already working! :slight_smile:

The documentation also says something about prioritizing the IPTV traffic with value 5 (802.1p). Any idea how I can implement this in openwrt?