Hello Alil,
Attempt state is only valid on nonbrodcast networks, where it indicates that hello packet was sent towards specific nehighbor, but router still havent received any hello from the specific neighbor. You can lab this using GNS3 by telling OSPF to threat Ethernet interface as Non-Broadcast and specify neighbor with ip address in same subnet.
Imagine following scenario with one switch and one router. The switch is there only to allow interface g0/0 on R1 to be in up/up state. There are not any other routers connected to the switch.
Configuration like this:
R1# show run | section Ethernet0/0|ospf
interface GigabitEthernet0/0
ip address 192.168.1.1 255.255.255.0
ip ospf network non-broadcast
media-type rj45
router ospf 1
network 192.168.1.1 0.0.0.0 area 0
neighbor 192.168.1.2
produces stuck in Attept state.
R1# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
N/A 0 ATTEMPT/DROTHER - 192.168.1.2 GigabitEthernet0/0
Producing stuck in Loading state can be more challenging. You can simulate it with this easy topology.
The key is to set mtu on switch interface to certain value. This value has to be big enough to let OSPF DB Descriptors pass but small enough to drop LS Update. This is why transit switch has mtu of 150 on its g0/1 interface. Because R1 has 8 loopback networks that need to be advertised to R2, the LS Update is going to have 194 bytes and this size causes transit switch in the middle to drop this LS Update.
Here is basic config of R1.
R1# show run | section router ospf
router ospf 1
router-id 0.4.0.1
limit retransmissions non-dc disable
network 10.0.0.0 0.0.7.255 area 0
network 192.168.12.1 0.0.0.0 area 0
R1# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
0.4.0.2 1 FULL/BDR 00:00:36 192.168.12.2 GigabitEthernet0/0
In this case, adjacency state on R1 is FULL, because it has everything it needs from R2, but R2 is going to have adjacency in Loading state, because it requires LS Update from R1 and this update is not getting to him, thus R2 continues to retransmit LS Request and R1 is continuing to retransmit LS Update (which is being dropped).
By default retransmission limit is set to 25 and then neighborship is dropped, to make R2 stay in Loading state forever we disabled this limit.
R2# show run | section router ospf
router ospf 2
router-id 0.4.0.2
limit retransmissions non-dc disable
network 192.168.12.2 0.0.0.0 area 0
R2# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
0.4.0.1 255 LOADING/DR 00:00:35 192.168.12.1 GigabitEthernet0/3
This example is not so practical, but I hope it serves your needs.