Re: [gpsd-dev] Draft Stratum 1 Microserver HOWTO is up

[Gary E. Miller]

Yo Eric!

Serious progress!

On Tue, 24 May 2016 10:46:32 -0400
"Eric S. Raymond" <address@hidden> wrote:

> Gary E. Miller <address@hidden>:
> > Great progress, but...
> > 
> > It could use some photos, got a smart phone with camera?  
> 
> There is now one photo, of the blue-wire mod required for the Chinese
> board. What others would you suggest?

Maybe one that shows 'North Up" ?

> > Typo:
> > 
> > "Uputronics board snugs ino an on-board fitting and"
> > 
> > ino -> into  
> 
> Already fixed.

Yeah, since you took so long to get to my email.  :-)

>     Note: your host may automount the card if it has been set up for
>     Linux before - whether this happens depends on what distribution
>     and desktop environment you are using. If your window manger pops
>     up a file-browser view of the device, you should unmount it
>     through that GUI.

A common case, but not definitive.  Why do you avoid directly telling the
user to check df and mount commands?

> > ddimage could unzip to stdout and save some disk space:
> > 
> > unzip -c 2016-03-18-raspbian-jessie-lite.zip | ddfldd bs=4M
> > of=/dev/sdd  
> 
> Disk space is cheap. Waiting is expensive.  I'd ratther conditionally
> unzip if the img file isn't already present.

Which increases waiting.  Uncompressing and dumping a zip file is
usually faster than dumping the same file uncompressed.  You are limited
by disk speed, not unzip speed.

But not a big deal either way.  I was in a space contrained environment
so it mattered to me.


> > "You should see NMEA0183 sentences issuing in bursts once per
> > second"
> > 
> > example?  
> 
> I didn't try because you can't really convey the burst timing in
> print.

True, but the newbie may not know wheat NMEA looks like.

> I don't want to wire in assumptions about the GPS type here,
> especially since we're supporting three different types. There should
> be an Advanced Topics section - not yet written - about computing a
> fudge. 

Fair enough.

> That's in the config --install stage.  Remember, one goal of this
> procedure is minimizing reversibility effort until we know the
> software works.

One can always reinstall ntpd classic.  But not a big deal either way.

> > # gpsd/gpsd /dev/gpsd0  
> 
> I did not.  It's forced in the timeserver build.

Ah, OK.  Maybe we can get it in all gpsd buids soon?  :-)

> > "Install the pinup script:"
> > 
> > Uh, I don't have that??  
> 
> You do.  clocmaker --build copies it in.  If it doesn't, update your
> copy.

You linked to it later in the doc, prolly should be linked in the
first usage.

> > "On the SBC, create an account for "me" (whatever username you like)
> > using adduser run as root."
> > 
> > I have seen windows hosts hacked in minutes after going live.  Do
> > this WAY earlier in the process.  
> 
> I think this is over-paranoid.  Your Pi is not an Internet-facing
> machine;

Uh, mine are internet facing.  And for those lucky to have IPv6, even if
they have NATed IPv4 they have public IPv6!  This surprises many people.

I what my logs carefully, even the NSA warns me not to.  :-)

Many times a day I see people trying the default pi login.  Three times
in the last hour!

> Again, the reason I moved this to late in the sequence is to minimize
> user hand-work before the point where we know the build would work.
> I consider that important.

And I consider getting hacked more important.  Seen it happen too many
times.  This is "NTPsec" right?  Or am I in the wrong place?

> > "Don’t be overly concerned if ntpq -p initially shows large jitter.
> > "
> > 
> > Examples of good and bad?  
> 
> Please supply and explain them. I'm still not sure of my ability to
> tell the difference.

I'll ponder some good ones.
 
> > I find perple get "pstree -paul" a lot quicker.  
> 
> Good point.  Now says "as you can verify by running "pstree -paul" (or
> the older-school "ps ax")"

Or maybe "pstree -paul | less"

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        address@hidden  Tel:+1 541 382 8588

pgp0TZ7MgS2da.pgp
Description: OpenPGP digital signature