The long name is just too hard to type. We generally should avoid using
acronyms too liberally, if they aren't established enough, but it appears that
"RA" is known well enough. Internally we call the option "ipv6_accept_ra"
anyway, and the kernel also exposes it under this name. Hence, let's rename the
IPv6AcceptRouterAdvertisements= setting and the
[IPv6AcceptRouterAdvertisements] section to IPv6AcceptRA= and [IPv6AcceptRA].
The old setting IPv6AcceptRouterAdvertisements= is kept for compatibility with
older configuration. (However the section [IPv6AcceptRouterAdvertisements] is
not, as it was never available in a published version of systemd.
Write comments about "too many search domains" and "Total length of all search
domains is too long" just once. Also put it on a separate line, as
resolv.conf(5) only specifies comments in a line by themselves.
This is ugly to do if write_resolv_conf_search() gets called once for every
search domain. So change it to receive the complete OrderedSet instead and do
the iteration by itself.
Add test cases to networkd-test.py.
https://launchpad.net/bugs/1588229
This uses temporary configuration in /run and temporary veth devices, and does
not write anything on disk or change any system configuration; but it assumes
(and checks at the beginning) that networkd is not currently running.
This can be run on a normal installation, in QEMU, nspawn, or LXC.
As this requires root privileges, this is not integrated into "make check".
