On Wed, Mar 11, 2020 at 5:52 PM Mantas Mikulėnas <graw...@gmail.com> wrote: > > Well, are you asking about the *source* port or about the *destination* port? > There are two on every UDP packet.
Sorry, of course source port - I spent so much time trying to synchronize time using systemd-timesyncd and ntpdate that I couldn't think about any other port - well, context is everything. > The source port is *not* from the privileged range -- systemd-timesyncd > always just lets the OS choose a random port from the ephemeral range. (I > have seen some other NTP clients such as Windows insist on using 123 as both > source and destination, but that's not the case with systemd-timesyncd nor > with most other SNTP clients.) Ok, this seems to be an obvious solution - yet ntpd and ntpdate by default bind to local 123 port - I see that systemd does the sensible thing. > The destination port has to be from the privileged range (specifically 123) > because that's what NTP servers *listen on* -- the client cannot decide on a > different port entirely on its own; you'd need to run your own NTP server > configured to use a different port. Yes. > Although if you already have an NTP server listening on a different port, > then unfortunately no, systemd-timesyncd does not currently have a config > option for that. It seems port 123 is hardcoded in manager_connect(), most > likely because that's what every public NTP server uses. No, this is Windows server and I after running `ntpdate -u <ip>` I can synchronize time just fine. Now one more question - I read that to run properly, systemd-timesyncd needs systemd-networkd successfuly started. This is true in my case - systemd-networkd reports success. I have server IP set in `/etc/systemd/timesyncd.conf` file like this: [Time] NTP=<IP> Note that these devices run Debian 9.4, so not only old version, but also distribution that isn't known for being on cutting edge. And one more question: what is systemd-timedated? It seems that is exactly same thing, but I don't think this is true? Thanks in advance, JD > (Really I can't really think of any good purpose for such a block -- if > anything, I'd expect to see the opposite, i.e. services on low ports allowed, > the rest blocked. Does your network block DNS on port 53, too?) > On Wed, Mar 11, 2020 at 6:34 PM Jędrzej Dudkiewicz > <jedrzej.dudkiew...@gmail.com> wrote: >> >> Hi, >> >> I have quite a few devices running Linux in client's network - so I >> have no control over it. It seems that all privileged UDP ports are >> blocked I have to use unprivileged port. I'd like to use >> systemd-timesyncd to synchronize time, thought I can't find a way to >> force it to use unprivileged port. Is there any way to do it? >> >> Thanks in advance, >> -- >> Jędrzej Dudkiewicz >> >> I really hate this damn machine, I wish that they would sell it. >> It never does just what I want, but only what I tell it. >> _______________________________________________ >> systemd-devel mailing list >> systemd-devel@lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/systemd-devel > > > > -- > Mantas Mikulėnas -- Jędrzej Dudkiewicz I really hate this damn machine, I wish that they would sell it. It never does just what I want, but only what I tell it. _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
