On 2022-05-09, Stuart Henderson <[email protected]> wrote: >>> >>> That doesn't seem like correct behavior (the ISC version certainly >>> offers both). Both options should be sent if configured, it's up to >>> the client to properly handle this. >>> Clients that are rfc3442 compliant will install the option 121 routes, >>> clients that are not rfc3442 compliant will ignore option 121 and >>> install the gateway supplied by option 3. If dhcpd doesn't hand out >>> option 3 when option 121 is configured then clients that are not >>> rfc3442 compliant will not receive a gateway address. >> >>> >> I fully agree, I was very surprised when I discovered this >> behaviour. But I haven't chased it down why this is. > > It was done to work-around broken clients: > > https://github.com/openbsd/src/commit/3f461432d6a77eea41f084ef892403cacc2ee370
...so the correct configuration is clear: list both a 0.0.0.0/0 classless route and "option routers", and it should work for all cases.
