Add static DHCP entry
# create new entry
uci add dhcp host
uci set dhcp.@host[-1].name='srv1'
uci set dhcp.@host[-1].mac='00:01:02:25:96:99'
uci set dhcp.@host[-1].ip='192.168.2.55'
uci commit dhcp
# restart dhcpd server
/etc/init.d/dnsmasq restart