topic NPT Server - Local no internet connection in Operating System - Linux

NPT Server - Local no internet connection

KarloChacon — Sat, 13 Feb 2010 21:56:50 GMT

hi guys

since I got a secure area my linux servers don't not have internet connection at all...

so I've configured an NTP Linux server with this configuration but my NTP Linux Client are not syns the time with the NTP Server

network: 192.168.3.0

1. I sync my NTP server to itselft
# ntpdate -du ntpserver
#service ntpd start
2. I syn my linux clients
# ntpdate -du ntpserver
ntp service for clients is stop

now my NTP server configuration

--------------------------------------------
restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery

restrict 127.0.0.1
restrict -6 ::1

restrict 192.168.3.0 mask 255.255.255.0 nomodify notrap

broadcastclient # broadcast client

server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 10

driftfile /var/lib/ntp/drift

keys /etc/ntp/keys

--------------------------------------------

when I run to sync my clients
#ntpdate -du ntpserver
results see the last line it says client is not sync by 87 secs...so what I have to do? which command so the time in my NTP client is the same as my NTP server?

13 Feb 15:19:14 ntpdate[7820]: ntpdate 4.2.2p1@1.1570-o Thu May 14 13:00:58 UTC 2009 (1)
Looking for host ntpserver and service ntp
host found : ntpserver
transmit(192.168.3.2)
receive(192.168.3.2)
transmit(192.168.3.2)
receive(192.168.3.2)
transmit(192.168.3.2)
receive(192.168.3.2)
transmit(192.168.3.2)
receive(192.168.3.2)
transmit(192.168.3.2)
server 192.168.3.2, port 123
stratum 11, precision -20, leap 00, trust 000
refid [192.168.3.2], delay 0.02582, dispersion 0.00012
transmitted 4, in filter 4
reference time: cf2195ee.d011023f Sat, Feb 13 2010 15:19:42.812
originate timestamp: cf219629.6559ce6f Sat, Feb 13 2010 15:20:41.395
transmit timestamp: cf2195d2.35601ffb Sat, Feb 13 2010 15:19:14.208
filter delay: 0.02824 0.02586 0.02582 0.02585
0.00000 0.00000 0.00000 0.00000
filter offset: 87.18836 87.18729 87.18728 87.18726
0.000000 0.000000 0.000000 0.000000
delay 0.02582, dispersion 0.00012
offset 87.187280

13 Feb 15:19:14 ntpdate[7820]: step time server 192.168.3.2 offset 87.187280 sec

thanks a lot

Re: NPT Server - Local no internet connection

Steven E. Protter — Sun, 14 Feb 2010 03:55:02 GMT

Shalom,

Most Corporate network environments do not provide wide open access on port 123 to time servers.

You may wish to find out your local time server and configure to use them.

SEP

Re: NPT Server - Local no internet connection

KarloChacon — Sun, 14 Feb 2010 05:29:54 GMT

well I managed these servers but I did not installed them but who did it completely disabled firewall on linux servers

If I am not wrong my NTP server is listening on 123

http://i50.tinypic.com/bi8cwl.jpg

Re: NPT Server - Local no internet connection

KarloChacon — Sun, 14 Feb 2010 22:33:03 GMT

well guys I think is working now

to tell you the truth is was like using -u instead of -du was the thing why my clients did not sync with the NTP Server

I added my conf in case any comment is appreciate it

Re: NPT Server - Local no internet connection

BUPA IS — Fri, 19 Feb 2010 16:37:20 GMT

Hello,
Some comments on your notes
For general use for NTP 4.2 you can replace this lot
> # 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
with
# allow this server continue to serve time when no outside source is available
tos orphan 10

If this server becomes isolated from all other NTP servers it will drop to stratum 10 (or whatever number you use) and continue by using its own local clock until a peer or server relationship is restablished .

You might want to add the NTP documentation link
http://www.eecis.udel.edu/~mills/ntp/html/index.html

and the ntp development site
http://www.ntp.org/

Mike

Re: NPT Server - Local no internet connection

KarloChacon — Fri, 19 Feb 2010 17:20:02 GMT

thanks BUPA for taking your time to check my notes

for sure I will be adding that additional info

Re: NPT Server - Local no internet connection

Steven E. Protter — Fri, 19 Feb 2010 19:38:37 GMT

Shalom,

You are correct, ntp listens on port 123.

As a short term back up, local clock will due.

Computer server clocks are noteworthy in how badly they keep time, so you can not rely on this more than a few hours at best.

telnet timesource 123

To test connectivity and firewall settings.

If your firewall is Linux based, you can probably set it up to be your office time server.

SEP