Hi, on my (ISC-)DHCP-server I see DHCPDISCOVER pakets coming from my RB4011 every second. The thing is, there is no DHCP(v4) client configured on the router, so it should not be doing DHCP requests at all. There is just a DHCPv6-client for my Internet connection, which is on PPPoE tunnel on a different VLAN on the same interface.
[admin@RB4011] > /ip/dhcp-client/export
# may/24/2021 17:38:54 by RouterOS 7.1beta6
# software id = CTSI-ABQQ
#
# model = RB4011iGS+
# serial number = XXXXX
[admin@RB4011] >
[admin@RB4011] > /ipv6/dhcp-client/export
# may/24/2021 17:39:35 by RouterOS 7.1beta6
# software id = CTSI-ABQQ
#
# model = RB4011iGS+
# serial number = XXXXX
/ipv6 dhcp-client
add add-default-route=yes interface="WTNet PPPoE" pool-name="WTNet Pfx" pool-prefix-length=56 rapid-commit=no request=\
address,prefix use-peer-dns=no
[admin@RB4011] >