Hi,

I have some trouble with "ip verify unicast source reachable-via " command.

I've well understood the difference between "ip verify unicast source 
reachable-via rx" and "ip verify unicast source reachable-via any". The first 
one is a strict mode and check the source is well reachable via the receiving 
interface while the second just check the source has a route in the FIB. 

But where I'm a bit lost is when you add an ACL after the command. The 
documentation says the ACL is checked if the uRPF fails, if the source IP 
matches a deny statement the packet is dropped, if it matches a permit 
statement it is forwarded even though it failed the uRPF. I think I've 
understood that part but I seem unable to make it work on real gear…

Here is what I did:

R1---(f0/1) R2 (f0/0)---R3

R1 and R3 have a loopback 200.0.0.1/32
R1 advertise it to R2,
R2 advertise it to R3,
R3 do not advertise it to anyone.

If I ping R2's loopback (200.0.0.2) from R3 with 200.0.0.1 as source, I see 
that packet arriving on int f0/0 and response are going out to f0/1. (Normal)

If I configure "ip verify unicast source reachable-via rx" on R2's f0/0 
interface, the packet are simply dropped.

Now If I configure "ip verify unicast source reachable-via rx 1" and 
"access-list 1 permit any log", I would expect the packet to not be dropped but 
only logged and the response to be sent out interface f0/1 as without uRPF at 
all. However R2 still drop the packets and do not log anything…

Did I miss something? 

Best regards,
Christophe
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