[Dnsmasq-discuss] Multiple interfaces responding to DHCP requests

[Nick Howitt]

On 13/05/2021 21:01, Horn Bucking wrote:
> According to dnsmasq documentation, it would seem neither dhcp-option 
> nor dhcp-range (at least for IPv4) would accept an interface:
> 
> -O, 
> --dhcp-option=[tag:<tag>,[tag:<tag>,]][encap:<opt>,][vi-encap:<enterprise>,][vendor:[<vendor-class>],][<opt>|option:<opt-name>|option6:<opt>|option6:<opt-name>],[<value>[,<value>]]
> 
> -F, 
> --dhcp-range=[tag:<tag>[,tag:<tag>],][set:<tag>,]<start-addr>[,<end-addr>|<mode>][,<netmask>[,<broadcast>]][,<lease 
> time>]
> 
> 
> However, dnsmasq would auto-tag DHCP requests with "a tag whose name is 
> the name of the interface on which the request arrived".
> 
> Did you try to prefix your interface names with the 'tag:' keyword?
> E.g.
> 
> dhcp-option=tag:enp2s0,1,255.255.255.0
> dhcp-range=tag:enp2s0,192.168.1.100,192.168.1.199,infinite
> 
The file is generated by the webconfig in ClearOS (based on Centos) and 
has been for years and no one has ever reported an issue with this. 
There are heaps of installations including mine. I can try overriding it 
manually.