How to Update Date and Time With out Internet

[udara]

I have connect my RPi to LAN but there is no internet available so is there any method to update RPi date time by using a PC in LAN. I want to get computer date and time to my RPi when it booting.
Thanks.

[Joe Schmoe]

Lots of ways to do this, but the key questions are:

1) What OS is your PC running?

2) How much programming are you willing/able to do?

[udara]

I'm using Windows 7 on my PC and I'm not an expert on programming but I think I can handle.

[udara]

Is it possible to start a NTP server in my PC and then add its IP address in raspberry pi ntp pool.
Thanks.

[ame]

Is it possible to start a NTP server in my PC and then add its IP address in raspberry pi ntp pool.
Thanks.

That's a great idea. You should try it!

[r3d4]

pi + camera + sundial !
Then just create some sundial tracking software/app's ,.. done .

That or some kind of http://en.wikipedia.org/wiki/Radio_clock ?
Now i iread fully your question you want to update 'With out Internet' but with LAN ! .
Guess the pi-sundial was never met to be ;P

[Joe Schmoe]

The key thing in this thread is that the work has to be done on the Windows side.

Once you have some kind of server running on the Windows, the Pi side is trivial.

Unfortunately, no one here is likely to want to help you with Windows problems.

[udara]

Thanks for the ideas.
I found out few options update raspberry pi date time without internet.
1. Starting NTP server in a PC. http://social.technet.microsoft.com/For ... inserverPN
2. Using a RTC module. http://afterthoughtsoftware.com/products/rasclock
Mainly I'm try to start a NTP server in PC.
Thanks.

[Joe Schmoe]

Mainly I'm try to start a NTP server in PC.
Thanks.

If you can get this working, let us all know. It could be useful.

If not, I have a few "roll my own" solutions that I've created and used over the years.

[hippy]

One option may be to use a TCP 'daytime' server and client rather than NTP. If not already present ( check Simple TCP/IP Services under Windows ), client or server should be fairly trivial to code, the Windows server software probably easier than the client.

[udara]

I enabled NTP server from windows registry and enabled time service from administrative tools - services and then I open TCP and UDP port 123 then I add my pc ip address to ntp.conf but it didn't work.
I would really appreciate if someone can give me some points or a different method to do this.
Thanks.

[Joe Schmoe]

I enabled NTP server from windows registry and enabled time service from administrative tools - services and then I open TCP and UDP port 123 then I add my pc ip address to ntp.conf but it didn't work.
I would really appreciate if someone can give me some points or a different method to do this.
Thanks.

The problem is that all solutions are basically equivalent - they all require mucking about in Windows, and defeating all the lame-o "security" mis-features of Windows. I have no doubt that if you mucked with it long enough, you could get NTP working under Windows. But you would feel dirty for having done so.

My preferred solution is to run an rdate server (Cygwin-compilable source is attached - that is, if I can get the attachment feature working on this brain-dead board software…) on the Windows box and use rdate (available via "apt-get install rdate") on the Pi side.

[sprinkmeier]

I enabled NTP server from windows registry and ...

problem == opportunity to learn something new

Run this on the machine that knows what time it is:

Code: Select all

import socket
import time
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
while 1:
    s.sendto(str(time.time()), ('255.255.255.255',55555))
    time.sleep(10-(time.time() % 10))

It broadcasts the current time every 10 seconds over UDP.
Then you run this on the system that wants to learn the time:

Code: Select all

import socket
import time
import os
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind(('',55555))
while 1:
    l = s.recv(100)
    t = float(l)
    d = t - time.time()
    if (abs(d) > 1):
        os.system('echo sudo date %s' % time.strftime('%m%d%H%M%Y.%S', time.localtime(t)))
    else:
        print(l,t,d)

It will print out the date command necessary to set adjust the time.
Try it, and if it seems to be doing the right thing take out the echo and it will set the time automagically.

No, this is not the easiest way to do it, but it is going to teach you a few things about python, UDP, startup scripts, ...

[ame]

Here you are:
http://www.satsignal.eu/ntp/setup.html

I enabled NTP server from windows registry and enabled time service from administrative tools - services and then I open TCP and UDP port 123 then I add my pc ip address to ntp.conf but it didn't work.
I would really appreciate if someone can give me some points or a different method to do this.
Thanks.

[udara]

Thanks for the replies,
Now I think NTP service is running on my pc,
http://windowsforum.com/threads/windows ... ost-159346
http://javadotnet.in/2013/01/create-you ... windows-7/
I checked with following python code

Code: Select all

import ntplib
from time import ctime

c = ntplib.NTPClient()
response = c.request('192.168.1.100', version=3)
#response = c.request('europe.pool.ntp.org', version=3)

print response.offset
print response.version
print ctime(response.tx_time)
print ntplib.leap_to_text(response.leap)
print response.root_delay
print ntplib.ref_id_to_text(response.ref_id)

when I run this code in RPi it gives following out put in screen shot. Then I add ip address to ntp.conf

Code: Select all

server 0.192.168.1.100

but RPi is not update its date time automatically. Is this the correct way to change ntp.conf ?
I think it is possible to set date time by using

Code: Select all

date -s <date string> 

If RPi not update automatically I'm thinking get date and time using this code and then update RPi date and time when booting, Is this possible ?
Thanks.

[morgad]

try

Code: Select all

server 192.168.1.100 iburst

(there was an extra 0. at the front)
iburst added for faster start-up

best regards
Dave

[udara]

Thanks.
I changed it but it didn't work.
When RPi update its date time? at start up only or any time when internet available?
Thanks.

[sprinkmeier]

If so then

Now I think NTP service is running on my pc,

It may be running, but it's probably not serving the time, or it's being firewalled or something silly.

try ntpq -np on the pi and post the result. It should look something like:

Code: Select all

$ ntpq -np
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+27.54.95.12     233.171.100.138  3 u   92 1024  377   85.189   -7.976   7.993

try running

Code: Select all

tcpdump -npi any udp port 123

on the Pi.
You should eventually see somthing like

Code: Select all

$ sudo tcpdump -npi any udp port 123
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on any, link-type LINUX_SLL (Linux cooked), capture size 65535 bytes
14:53:33.794425 IP 192.168.1.93.123 > 27.54.95.12.123: NTPv4, Client, length 48
14:53:33.889467 IP 27.54.95.12.123 > 192.168.1.93.123: NTPv4, Server, length 48

(with different IP addresses, but you get the idea...)

My guess is that the last line will be missing, i.e. the Pi will ask for the time but Windows won't respond.

[udara]

Thanks for the reply,
I ran those commands (in screen shot) and I think there is version mismatch if I'm right how can i resolve it or is it a different issue?
Thanks.

[DougieLawson]

Your time server at 192.168.1.100 is not answering any UDP time queries on port UDP 123.

So take a look at that machine; is it running an NTP server? is that server set-up to allow peering or remote clients? does that server have a firewall that blocks inbound requests on port UDP 123?

[sprinkmeier]

Thanks for the reply,
I ran those commands (in screen shot) and I think there is version mismatch if I'm right how can i resolve it or is it a different issue?
Thanks.

(text cut-and-paste will do fine, no need for a graphical screnshot).

OK... the "st" is stratum, lower is better.
Stratum 0 is a GPS-loocked clock, or some other type of very accurate referance.
stratum 16 is "I have no clue what time it is".
The ".init." in the ntpq command means "don't bother me yet, I haven't figured out what time it is"
So... the server isn't ready to provide time because it knows that it does not have a reliable referance.
There's a way to make it pretend. On Linux you would add something like this:

Code: Select all

# Undisciplined Local Clock. This is a fake driver intended for backup
# and when no outside source of synchronized time is available.
server  127.127.1.0     # local clock
fudge   127.127.1.0 stratum 10

in /etc/ntp/conf
Not sure how to do it on Windows (might be the same, don't have a windows box to test with).

[udara]

Thanks for replies,
I tried out different ways setup a NTP server
1. http://nts.softros.com/ this is a great server and raspberry pi automatically update date and time unfortunately it need license.
2.As "ame" suggest http://www.satsignal.eu/ntp/setup.html this is free and work nicely but some times RPi take about 30s to update its date and time.
So I'm thinking to use 2 option but still try to configure NTP service in windows 7.
Thanks.

[Joe Schmoe]

Were you able to compile and use the rdate_server program?

That's clearly the easiest way to do this - instead of all this mucking with the guts of the ntp* programs.

[ame]

Were you able to compile and use the rdate_server program?

That's clearly the easiest way to do this - instead of all this mucking with the guts of the ntp* programs.

The easiest way to do it is to get the well-known, standards-based programs working.

[sprinkmeier]

Were you able to compile and use the rdate_server program?

That's clearly the easiest way to do this - instead of all this mucking with the guts of the ntp* programs.

The easiest way to do it is to get the well-known, standards-based programs working.

Start with the PC's OS :-)

http://www.debian.org/