On 2020/04/30 20:32, Gerhard Roth wrote: > Hi Theo, > > is umb really working that differently for a P2P interface? I think it is > very similar to ppp(4) and IPv6. The standard way is to obtain the IP > address via PPP protocol. Just like this, umb(4) obtains the IP address via > MBIM protocol.
PPP is quite different, it only negotiates a link-local v6 address. If you want a routable address you must use slaac, dhcpv6, or static config. > That's what is implemented with this and former umb(4) patches. With the > current patch you can just do "ifconfig umb0 inet eui64" or "ifconfig umb0 > -inet6" anytime, whether the interface is up or not. > > But then there seem to be strange ISPs in Japan as detected by job@. They > don't provide any IPv6 address via MBIM protocol but rather use the standard > IPv6 SLAAC protocol. It strange; just as if ppp(4) would need DHCP to obtain > its IPv4 address. But still, it seems to exist and users can still work with > umb(4) if they do "ifconfig umb0 inet6 autoconf". What happens if an ISP provides a v6 address via MBIM-config and the interface is set to "inet6 autoconf", does it still work OK? That's what most people will try. Since we disabled IPv6 by default, IPv6 users already know how to use "inet6 autoconf". > > I also feel noone is going to read the manual page, find this piece > > of text, and understand it. Honestly, I don't understand this piece > > of text. I'm not going to set the AUTOCONF6 flag. How does one even > > set it? > > > > ifconfig: AUTOCONF6: bad value > > > > Of course not, but I am ironically trying to show this documentation > > chunk doesn't help at all. People can't act upon it properly. > > > > I still argue umb's inet6 should work absolutely as much like regular > > interfaces, or it is useless. People are not going to treat this > > interface differently and then gain successful inet6. If inet6 can't > > work naturally and easily, but instead is a special snowflake, that > > is just plain dumb. Unfortunately mobile data is a special snowflake because you get some providers who say "to conserve licenses with the network vendor you can have either an IPv4 address or an IPv6 address but not both at the same time" so you need a way to do something which isn't required on normal ethernet. > > > > +.Pp > > > > +To use IPv6, configure a link-local address. > > > > +If the device is able to connect to the ISP's network but doesn't > > > > +show an IPv6 address, setting the > > > > +.Sy AUTOCONF6 > > > > +flag on the interface before bringing it up may help. > > > > +.Ed Showing the actual command to type will help a lot here. On 2020/04/30 20:52, Gerhard Roth wrote: > It it too much to expect users to read the ifconfig man page? Printed, it is 28 pages of A4. Compare with the wifi drivers, you have to look at ifconfig(8) if you want all the details, but EXAMPLES in iwm(4) (and I think all the other drivers) is enough for a quick bare-bones config. That seems a reasonable model.
