On Nov 30, 2013, at 5:34 PM, Richard Cochran <[email protected]> wrote: > On Sat, Nov 30, 2013 at 10:35:25AM +0100, Delio Brignoli wrote: >> >> From memory, the problem was that when running in slave-only mode linuxptp >> didn't start announcing when the port became asCapable. According to 802.1AS >> we should be announcing ourselves immediately when the port becomes >> asCapable even if we do not support being master. > > AFAICT, the only part of 802.1AS-2011 that mentions when to transmit an > announce message is Figure 10-15 on page 84. On the right hand side > there is the state TRANSMIT_ANNOUNCE which calls the txAnnounce method.
Thanks for taking the time to look into this. See below for my comments. > That state is only reachable if (selectedRole == MasterPort), and so > it looks like we should not transmit when is slave only mode, just > like in 1588. Yes, but... 802.1AS does not have a different state machine for slave-only operation, instead a non grand-master capable time-aware system has a property1 value of 255 (see second paragraph of section 8.6.2.1). Additionally, according to point f.5 of section 10.3.12.1.4 updtRolesTree(), if the current portPriorityVector is the portPriorityVector of the time-aware system (i.e. we have not yet received an announce message with better portPriorityVector) the portRole should be set to MasterPort which makes the txAnnounce method reachable. Thanks -- Delio ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349351&iu=/4140/ostg.clktrk _______________________________________________ Linuxptp-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
