DHCP limit address range and disable IPv6?

[newshoes]

Hi I recently switched over to OpenWRT 19.07.0-rc2 from Tomato. In Tomato web interface there's a way to limit the DHCP address range. I cannot find anything similar in the LuCI web interface. I have various addresses in Virtual Machines that are statically assigned and I don't want the DHCP server giving out those addresses, so I need to limit the range to .100 - .149 if it does not do that already.

Also I want to disable IPv6. I found directions in this forum several days ago that suggested:

cat >> /etc/sysctl.conf
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1

However despite that I still have a WAN6 with an IPv6 address and I am seeing these two DHCP errors continually in the log:

Sat Nov 30 16:23:53 2019 daemon.err odhcpd[846]: Failed to send to ff02::1%lan@br-lan (Permission denied)
Sat Nov 30 16:25:26 2019 daemon.err odhcp6c[1105]: Failed to send DHCPV6 message to ff02::1:2 (Permission denied)

Short of creating a special build with IPv6 disabled how can I shut it off? Thanks

[aboaboit]

I'd say Network -> Interfaces -> Wan -> "Use builtin IPv6-management" (uncheck)

The DHCP range is under Network -> Interfaces -> LAN -> Start / Limit

[trendy]

You can just delete the wan6 interface, untick boxes for IPv6, disable IP6ASSIGNMENTS, disable RAs and DHCP6D. However full removal of IPv6 is not a supported configuration.

Why are there barely any tutorials?

This is not considered a supported OpenWrt configuration anymore.

[newshoes]

Ok thanks guys. I've made these changes:

LAN > Advanced > UNCHECK: Use IPv6-management
LAN > DHCP > General > Start > 100
LAN > DHCP > General > Limit > 50 (Log confirms this sets the range to 100-149)
LAN > DHCP > IPv6 > Disable everything
WAN > Advanced > UNCHECK: Use IPv6-management
WAN6 > Delete

@trendy

However full removal of IPv6 is not a supported configuration.

During the first two minutes of startup there's still IPv6 messages from the router (multicast listener and router solicitation) but after that nothing which for my purposes is fine.

[trendy]

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