It seems that v7.12 stable will not generate OSPF LSA type3 - “inter-area-prefix“ while v7.11.2 stable is ok.
Here are configs:
[admin@ROS7.11.2A] >export
/ip address
add address=10.0.0.1/24 interface=ether1 network=10.0.0.0
add address=192.168.1.1/25 interface=ether2 network=192.168.1.0
/routing ospf instance
add disabled=no name=ospf-instance-1 router-id=192.168.1.1
/routing ospf area
add disabled=no instance=ospf-instance-1 name=BB
add area-id=0.0.0.1 disabled=no instance=ospf-instance-1 name=1
/routing ospf area range
add area=1 disabled=no prefix=192.168.1.0/24
/routing ospf interface-template
add area=BB disabled=no interface=ether1
add area=1 disabled=no interface=ether2
[admin@ROS7.11.2B] >export
/ip address
add address=10.0.0.2/24 interface=ether1 network=10.0.0.0
add address=192.168.2.1/25 interface=ether2 network=192.168.2.0
/routing ospf instance
add disabled=no name=ospf-instance-1 router-id=192.168.2.1
/routing ospf area
add disabled=no instance=ospf-instance-1 name=BB
add area-id=0.0.0.2 disabled=no instance=ospf-instance-1 name=2
/routing ospf area range
add area=2 disabled=no prefix=192.168.2.0/24
/routing ospf interface-template
add area=BB disabled=no interface=ether1
add area=2 disabled=no interface=ether2
[admin@ROS7.12A] >export
/ip address
add address=10.0.0.3/24 interface=ether1 network=10.0.0.0
add address=192.168.3.1/25 interface=ether2 network=192.168.3.0
/routing ospf instance
add disabled=no name=ospf-instance-1 router-id=192.168.3.1
/routing ospf area
add disabled=no instance=ospf-instance-1 name=BB
add area-id=0.0.0.3 disabled=no instance=ospf-instance-1 name=3
/routing ospf area range
add area=3 disabled=no prefix=192.168.3.0/24
/routing ospf interface-template
add area=BB disabled=no interface=ether1
add area=3 disabled=no interface=ether2
[admin@ROS7.12B] >export
/ip address
add address=10.0.0.4/24 interface=ether1 network=10.0.0.0
add address=192.168.4.1/25 interface=ether2 network=192.168.4.0
/routing ospf instance
add disabled=no name=ospf-instance-1 router-id=192.168.4.1
/routing ospf area
add disabled=no instance=ospf-instance-1 name=BB
add area-id=0.0.0.4 disabled=no instance=ospf-instance-1 name=4
/routing ospf area range
add area=4 disabled=no prefix=192.168.4.0/24
/routing ospf interface-template
add area=BB disabled=no interface=ether1
add area=4 disabled=no interface=ether2
I’ve opened a ticket in support portal, SUP-134571