troubleshooting Question

Understanding uRPF Loose Mode /Strict Mode,

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jskfanFlag for Cyprus asked on
RoutersSwitches / HubsNetwork Architecture
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Understanding uRPF Loose Mode /Strict Mode,

Let's say we have R1 connected on both of its 2 interfaces to R2 and R3
R1 interface IP address(192.168.12.1/24) connecting to R2
R1 interface IP address(192.168.13.1/24) connecting to R3

R2 interface IP address(192.168.12.2/24) connecting to R1
R3 interface IP address(192.168.13.3/24) connecting to R1

R2 has a loopback 0 with ip address 2.2.2.2/32

R1 has static route : Ip route 2.2.2.2 255.255.255.255 192.168.12.2

For test purpose I have created lopback 0 on R3 with the same IP address 2.2.2.2/32 as the loopback 0 on R2

With Strict Mode or Loose Mode configured, I can ping from R2 (source Loopback 0:2.2.2.2) to R1 (192.168.12.1)
I can see the ping replies. but I cannot ping from R3 (Source Loopback 0: 2.2.2.2) to R1 (192.16.13.1).
However when reading online, it states that with Loose Mode, R1 will accept packets from R3 and with Strict Mode it does not.
from my side, I still cannot see the difference between Strict/Loose Mode as both will cause Ping fails from R3 source loopback 0 to R1

Any clarification on this ?

Thank you
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