Re: [gpsd-users] Usind gpsd as ntpd source without PPS

[hans mayer]

hey henrik,

> But shouldn't unit 2 work in all cases?

i do not know.
maybe gary or somebody else can answer the question.
i wouldn't worry about security issues if unit 0 is working.

at least my shared memory looks like yours.
# ipcs -m
------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status
0x4e545030 0          root       600        80         2
0x4e545031 32769      root       600        80         1
0x4e545032 65538      root       666        80         1
0x4e545033 98307      root       666        80         1
0x4e545034 131076     root       666        80         1
0x4e545035 163845     root       666        80         1
0x4e545036 196614     root       666        80         1
0x4e545037 229383     root       666        80         1
0x47505344 262152     root       666        8928       1

for unit 0 and 1 read/write permissions are available only for root.
all others have full permissions.
but as i said, unit 2 does not work for me too.
i see my gpsd process is owned by user "nobody"

but i would take a 1PPS signal if possible.
between shared mem and 1PPS is a big difference.
attached 2 images.
127.127.28.0 is shared memory as you know.
here i am within a range of +-5 milli-seconds for the offset.
127.127.22.0 is a 1PPS from the same gps device.
the range is here between +- 10 micro-seconds.

schoene gruesse aus wien
hans

--




Am 27.02.2016 14:23, schrieb Henrik Bieler:
> Hey Hans,
>
> thank you for testing. Maybe I did give up on unit 0 too quickly.
> But shouldn't unit 2 work in all cases?
>
> Cheers
> Henrik
>
> Am 27.02.2016 um 12:22 schrieb hans mayer:
> > >
> > >
> > >hey henrik,
> > >
> > >i tried to reproduce your situation and configured just 1 source.
> > >
> > ># gpsd shared memory clock
> > >server 127.127.28.0 minpoll 5 maxpoll 6 prefer  # PPS requires at least
> > >one preferred peer
> > >fudge 127.127.28.0 refid GPS
> > >fudge 127.127.28.0 time1 +0.1495 flag4 1 # coarse processing delay offset
> > >#
> > >
> > >after short time it got synced.
> > >
> > ># ntpq -pn
> > >      remote           refid      st t when poll reach   delay   offset
> > >  jitter
> > >==============================================================================
> > >
> > >*127.127.28.0    .GPS.            0 l   16   32  377    0.000   -2.019
> > >5.665
> > >
> > >am using ntp 4.2.8p4 and gpsd 3.15
> > >
> > >but your problem is probably related using unit 2
> > >with this i didn't have success too.
> > >
> > >kind regards
> > >hans
> > >

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plot_15913.png
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