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Why do some icmp replies follow shortest links and some follow routing?

Why do some icmp replies follow shortest links and some follow routing?

Why do some icmp replies follow shortest links and some follow routing?

(OP)
5 Routers in a circle

R0- 1.1.1.0-R1- 2.2.2.0-R3- 3.3.3.0 -R4-4.4.4.0 - R0-5.5.5.0 (Router 0-1,2,3,4-Router 0)

R0 1.1.1.1 /24 ip route 0.0.0.0 0.0.0.0 1.1.1.2
5.5.5.2 /24

R1 1.1.1.2 /24 ip route 0.0.0.0 0.0.0.0 2.2.2.2
2.2.2.1 /24

R2 2.2.2.2 /24 ip route 0.0.0.0 0.0.0.0 3.3.3.2
3.3.3.1 /24

R3 3.3.3.2 /24 ip route 0.0.0.0 0.0.0.0 4.4.4.2
4.4.4.1 /24

R4 4.4.4.1 /24 ip route 0.0.0.0 0.0.0.0 5.5.5.2
5.5.5.1 /24

The problem:
A.When I ping from R0 to R1 1.1.1.2, appears to return icmp on 1.1.1.0 link. Direct link connect.
B.When I ping from R0 to R1 2.2.2.1, appears to return icmp on 1.1.1.0 link. Contrary to routing.
C.When I ping from R0 to R4 5.5.5.1, appears to return icmp on 5.5.5.0 link Direct link connect.
D.When I ping from R0 to R4 4.4.4.2, appears travel entire circle to R4, returns icmp back on 5.5.5.0 link.

To me, A is ok. B defies default routing. C is ok. Why doesnt D work like B

Thank you.

RE: Why do some icmp replies follow shortest links and some follow routing?

for part b if you source your icmp from 5.5.5.2 to 2.2.2.1 it should travel the circle.
otherwise B knows how to get back to 1.1.1.1 through its own interface...

We must go always forward, not backward
always up, not down and always twirling twirling towards infinity.

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