systemd has been the de facto standard for over a decade now and is very stable. I have found that even most people who complained about the initial transition are very welcoming of its benefits now.
Depends a bit on how you define systemd. Just found out that the systemd developers don't understand DNS (or IPv6). Interesting problems result from that.
> Just found out that the systemd developers don't understand DNS (or IPv6).
Just according to Github, systemd has over 2,300 contributors. Which ones are you referring to?
And more to the point, what is this supposed to mean? Did you encounter a bug or something? DNS on Linux is sort of famously a tire fire, see for example https://tailscale.com/blog/sisyphean-dns-client-linux ... IPv6 networking is also famously difficult on Linux, with many users still refusing to even leave it enabled, frustratingly for those of us who care about IPv6.
Systemd-resolved invents DNS records (not really something you would like to see, makes debugging DNS issues a nightmare). But worse, it populates those DNS records with IPv6 link local addresses, which really have no place in DNS.
Then, when after a nice debugging session why your application behaves so strangely, all the data in DNS is correct, why doesn't it work, you find that this issue has been reported before and was rejected as won't fix, works as intended.
Hm, but systemd-resolved mainly doesn't provide DNS services, it provides _name resolution_. Names can be resolved using more sources than just DNS, some of which do support link-locals properly, so it's normal for getaddrinfo() or the other standard name resolution functions to return addresses that aren't in DNS.
i.e. it's not inventing DNS records, because the things returned by getaddrinfo() aren't (exclusively) DNS records.
The debug tool for this is `getent ahosts`. `dig` is certainly useful, but it makes direct DNS queries rather than going via the system's name resolution setup, so it can't tell you what your programs are seeing.
systemd-resolved responds on port 53. It inserts itself in /etc/resolv.conf as the DNS resolver that is to be used by DNS stub resolvers.
It can do whatever it likes as longs as it follows DNS RFCs when replying to DNS requests.
Redefining recursive DNS resolution as general 'name resolution' is indeed exactly the kind of horror I expect from the systemd project. If systemd-resolved wants to do general name resolution, then just take a different transport protocol (dbus for example) and leave DNS alone.
It's not from systemd though. glibc's NSS stuff has been around since... 1996?, and it had support for lookups over NIS in the same year, so getaddrinfo() (or rather gethostbyname(), since this predates getaddrinfo()!) have never just been DNS.
systemd-resolved normally does use a separate protocol, specifically an NSS plugin (see /etc/nsswitch.conf). The DNS server part is mostly only there as a fallback/compatibility hack for software that tries to implement its own name resolution by reading /etc/hosts and /etc/resolv.conf and doing DNS queries.
I suppose "the DNS compatibility hack should follow DNS RFCs" is a reasonable argument... but applications normally go via the NSS plugin anyway, not via that fallback, so it probably wouldn't have helped you much.
If you don't like those additional name resolution methods, then turn them off. Resolved gives you full control over that, usually on a per-interface basis.
That's the main problem with systemd: replacing services that don't need replacing and doing a bad job of it. Its DNS resolver is particularly infamous for its problems.