Working on configuring ASA , where the ISP assigned outside IP:18.104.22.168/32 and gateway: 22.214.171.124.
This ASA will act as regular NAT device and L2L tunnel to another location.
My question is /32 on outside is good enough tfor doing this config.
Please review and suggest.
I suggest you double check with your ISP.
The info you have doesn't make sense.
A 32 bits subnet is a one address subnet , meaning a single host. But your outside interface needs to be in the same subnet than your default gateway. The smallest subnet possible here would be a /30 subnet, wich give 4 addresses (2 usable) .
But .67 and .69 are not part of the same /30 subnet. And .67 would be a broadcast address in a /30 ( 64-65-66-67).
So .67 and .69 can only be part of at least a /29 subnet ( 64-65-66-67-68-69-70)
But you have to verify thisa with your ISP because both devices needs to be configure with the same subnet.
/32 mask does not make any sense.
I agree that the mask ideally should be the same in both ends, but they don't need to. The ASA does not use the broadcast address.