> -----Original Message----- > From: Jord Pool [mailto:jord.p...@outlook.com] > Sent: Thursday, July 26, 2018 11:59 PM > To: Richard Cochran <richardcoch...@gmail.com>; Cliff Spradlin via Linuxptp- > users <linuxptp-users@lists.sourceforge.net> > Subject: Re: [Linuxptp-users] PXE Boot > > Hi all! > > As I explained in my previous email, when PXE booting, the PXE boot server > that > runs in slave mode will have it’s PTP slave instance interrupted, unless I > set the > tx_timestamp_timeout to ~200ms. Now what happens when booting more than > four server at the same time via PXE boot? Will I then have to increase the > tx_timestamp_timeout value again? This is not really the most practical way of > being able for the PXE boot server (PTP Slave) to keep synchronised. > > To solve the problem above, maybe there is a way to prioritise the PTP network > traffic so that it will not have any interference with servers booting > through PXE? > > Jord >
Hi Jord, The reason you need to increase the Tx timeout is that the driver you're using is taking too long to report the timestamp. It's almost certainly either a driver/hardware limitation, or a bug in the driver. Basically, ptp4l is sending a Tx packet with a timestmap request, and waits up to 1 millisecond for a response. But you increased this limit ot have it wait 200 milliseconds. This means that the driver is taking longer than 1 millisecond to send the packet, get the timestamp, and report it back... If it fails when the timeout is 200 milliseconds, then it's taking over 1/5th of a second to do this... What driver/hardware are you using? Thanks, Jake ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
