I've been searching information concerning the meaning of scopes both in addresses and routes but I don't understand the documentation I've read so far. This is what I've been reading:
- man 8 ip
- Source code of iproute2-4.5.0 (though I've lost familiarity with source code in C, so not much I got from this).
Is there other documentation I could read? Google for "iproute2 address scope" and similar was not helpful. What I thought an address scope would mean was how that address could be reached:
- "host": only from localhost.
- "link": only from other hosts directly attached to the network to which the corresponding device is attached to.
- "global": "host" + "link".
- Other scopes would be reserved for future usage.
I see no change in behavior if I change from "global" to "host", "link" or "3" the scope of the address my laptop is assigned through DHCP and the result was:
- In all cases I could ping from my laptop to that address and to the Internet.
- In all the cases I could ping from a virtual machine on the same laptop using a virtual NIC bridged to the same interface and with a manual network setup to that address.
Note that I'm only using IPv4.