Yes, CD-network is 192.168.4.0/24.
It is not in the same area, i redistribute this network with
protocols ospf redistribute connected
on C and D.
run show ip ospf database external adv-router 1.1.1.8
OSPF Router with ID (1.1.1.1)
AS External Link States
LS age: 632
Options: 0x22 : *|-|DC|-|-|-|E|*
LS Flags: 0x6
LS Type: AS-external-LSA
Link State ID: 192.168.19.0 (External Network Number)
Advertising Router: 1.1.1.8
LS Seq Number: 800065ca
Checksum: 0x3aad
Length: 36
Network Mask: /24
Metric Type: 2 (Larger than any link state path)
TOS: 0
Metric: 20
Forward Address: 0.0.0.0
External Route Tag: 0
Network 192.168.19.0 is redistributed in area 2, not 7. Don’t understand why it appears here.
run show ip ospf database external adv-router 1.1.1.14
OSPF Router with ID (1.1.1.1)
AS External Link States
LS age: 837
Options: 0x22 : *|-|DC|-|-|-|E|*
LS Flags: 0x6
LS Type: AS-external-LSA
Link State ID: 192.168.4.0 (External Network Number)
Advertising Router: 1.1.1.14
LS Seq Number: 8000012b
Checksum: 0x28cc
Length: 36
Network Mask: /24
Metric Type: 2 (Larger than any link state path)
TOS: 0
Metric: 20
Forward Address: 0.0.0.0
External Route Tag: 0