'Twas brillig, and Britton Kerin at 18/03/13 17:56 did gyre and gimble: > My service needs reasonably continuous mtimes on files, but at the > moment there is a big discontinuity soon after boot.
There is nothing you can do to rely on this absolutely. The only proper way is to fix the broken assumptions. Of course you can typically get a "good enough" result (tho' that doesn't make it any more correct, especially twice a year when daylight savings kicks in unless you're on a fixed timezone). > There are a number of web pages out there which tell you to put > stuff like this: > > After=syslog.target network.target > WantedBy=multi-user.target So this is written somewhat confusingly as these two directives go in different sections [Unit] and [Install] respectively. syslog.target is dead now so you don't need it any longer with any vaguely recent system. network.target is a bit rubbish too as the network is not really a static entity - it can appear to be 99.9% static. network itself has nothing to do with time. > In your .service file linked from: > > /etc/systemd/system/multi-user.target.wants > > I'm guess I want to be After one of these targets: > > time-sync.target or > systemd-timedated.service Yes, time-sync.target seems best. It's not a guarantee tho'. If there are network issues etc. then time-sync.target will be reached after a timeout if ntp tries and fails to update itself over the network. If the problem rectifies itself later (and this could be e.g. a routing issue totally outside of your server), then the ntp server should try and fix things. Of course most sensible ntp targets try to avoid big jumps and slow or speed the clock up a bit to bring it in line (please correct me if I'm wrong). > But if multi-user.target doesn't already depend on them I'm not sure its > safe for my target, which is WantedBy multi-user.target, to do so? You are confusing After and WantedBy here. The former is about ordering, the latter is about about grouping. WantedBy just means "I want this service to be started when multi-user.target starts" It doesn't contain any information about ordering etc. In an ideal world, everything wanted by multi-user.target would all be started in parallel. In practice, we typically want some degree of ordering, and that's what the Before= and After= directives are about. Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited http://www.tribalogic.net/ Open Source: Mageia Contributor http://www.mageia.org/ PulseAudio Hacker http://www.pulseaudio.org/ Trac Hacker http://trac.edgewall.org/ _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
