RE: Problem with NTP.





Hello Simon,
I have just run the tcpdump command on Eth0 as an
example and it returned tcpdump listening, capture size 96bytes so this
looks to be fine. The Answer to your other questions are below;

1). Yes we are using DHCP service on this machine with bond0.
2). ntpdate -q server1 = server server 1, stratum 4, offset -0.085034,
delay 0.05925
21 Apr 12:19:32 ntpdate[28633]: adjust time server
server1 offset -0.085034 sec
3)ntptrace = localhost.localdomain: stratum 16, offset 0.000000, synch
distance 0.056055
4)nsswitch.conf = services files nis
5)ypcat = 3694/tcp vpntpp 3694/tcp
119/udp nntp 119/udp readnews untp
563/udp nntps 563/udp
3346/udp trnsprntproxy 3346/udp
119/tcp nntp 119/tcp readnews untp
3346/tcp trnsprntproxy 3346/tcp
123/udp ntp 123/udp
563/tcp nntps 563/tcp
3079/udp lv-frontpanel 3079/udp
2514/udp facsys-ntp 2514/udp
2514/tcp facsys-ntp 2514/tcp
580/udp sntp-heartbeat 580/udp
3079/tcp lv-frontpanel 3079/tcp
1865/udp entp 1865/udp
3178/udp radclientport 3178/udp
123/tcp ntp 123/tcp
1865/tcp entp 1865/tcp
3178/tcp radclientport 3178/tcp
580/tcp sntp-heartbeat 580/tcp
5418/udp mcntp 5418/udp
5418/tcp mcntp 5418/tcp
3694/udp vpntpp 3694/udp
6). Yes there is a firewall but all hosts have access through it, hence 30
odd machines work currently.
7). Date/Timezone - Tue Apr 21 12:28:38 BST 2009

The interesting one for me out of all the things I have just run is the
ntptrace coming up as stratum16 which I would assume is like a non
communication, if i run this on a machine that works i get stratum 4.

Have a review of this info and let me know your thoughts.

Regards

Andrew Bridgeman




"Reber, Simon"
<simon.reber@roch
e.com> To
Sent by: "General Red Hat Linux discussion
redhat-list-bounc list" <redhat-list@xxxxxxxxxx>
es@xxxxxxxxxx cc

Subject
21/04/2009 12:04 RE: Problem with NTP.


Please respond to
General Red Hat
Linux discussion
list
<redhat-list@redh
at.com>






Andrew,

To make a try run with tcpdump, simply run tcpdump ... This will show
you the entire network traffic from this server.
To find out more about tcpdump, have a look at the man page:
http://linux.die.net/man/8/tcpdump

About the messages. Are I am right that you also run a DHCP services on
this host?
And is the interface you are working with bond0?
Do the other servers also have bonding interfaces?

Some other thoughts:
what does ntpdate -q server1 return?
what result does ntptrace return?
what shows cat /etc/nsswitch.conf | grep services
what shows ypcat -k services | grep ntp
Is there a firewall between localhost and server1
What's the date/time and timezone of the server

With the help of the above information, we should be able to fix the
problem (hopefully) ;-)

Cheers,
Simon

-----Original Message-----
From: redhat-list-bounces@xxxxxxxxxx
[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of
Andrew.Bridgeman@xxxxxxxxxxxxxx
Sent: Tuesday, April 21, 2009 12:42 PM
To: General Red Hat Linux discussion list
Subject: RE: Problem with NTP.



Hello Simon,
Thanks for help so far. I have checked and the
tcpdump package is installed with root permission's so in
theory we should
be able to run the tcpdump command. Is there an even simpler tcpdump
command to run just to check it can be used. Also I have
attached the last
25 minutes of the messages log, in which I have restarted the
ntpd service
to try and get it too synchronise. If you see anything to investigate
please let me know.

Apr 21 11:05:06 dhcpd: DHCPREQUEST for Server from
00:17:a4:f9:6f:fa via
bond0: unknown lease Server.
Apr 21 11:05:07 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:05:44 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:07:13 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:09:15 last message repeated 2 times
Apr 21 11:10:37 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:12:39 last message repeated 2 times
Apr 21 11:13:52 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:14:40 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:15:52 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:17:12 last message repeated 2 times
Apr 21 11:19:15 last message repeated 2 times
Apr 21 11:19:56 ntpd[26183]: ntpd Thu Nov 6 11:08:22 UTC 2008 (1)
Apr 21 11:19:56 ntpd[26184]: precision = 1.000 usec
Apr 21 11:19:56 ntpd[26184]: Listening on interface wildcard,
0.0.0.0#123
Disabled
Apr 21 11:19:56 ntpd[26184]: Listening on interface wildcard, ::#123
Disabled
Apr 21 11:19:56 ntpd[26184]: Listening on interface bond0,
fe80::21e:bff:fe60:acda#123 Enabled
Apr 21 11:19:56 ntpd[26184]: Listening on interface lo, ::1#123 Enabled
Apr 21 11:19:56 ntpd[26184]: Listening on interface lo, 127.0.0.1#123
Enabled
Apr 21 11:19:56 ntpd[26184]: Listening on interface bond0, Server#123
Enabled
Apr 21 11:19:56 ntpd[26184]: kernel time sync status 0040
Apr 21 11:19:56 ntpd[26184]: frequency initialized 0.000 PPM from
/var/lib/ntp/drift
Apr 21 11:20:10 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:21:13 dhcpd: BOOTREQUEST from 00:18:b1:4d:32:00 via
bond0: BOOTP
from dynamic client and no dynamic leases
Apr 21 11:23:12 last message repeated 2 times
Apr 21 11:25:01 last message repeated 2 times

Thanks

Andrew Bridgeman





"Reber, Simon"

<simon.reber@roch

e.com>
To
Sent by: "General Red Hat Linux
discussion
redhat-list-bounc list"
<redhat-list@xxxxxxxxxx>
es@xxxxxxxxxx
cc



Subject
21/04/2009 11:16 RE: Problem with NTP.





Please respond to

General Red Hat

Linux discussion

list

<redhat-list@redh

at.com>









Hi Andrew,

Well I think this is going to be a bit more difficult.
The "timeout" is coming obviously from the ntp settings set on server1
(noquery, etc.)

Anyway tcpdump is a tool to look at the network traffic and as
you said,
it is not possible to find the binary which usually indicates that it
isn't installed (try to run rpm -qa | grep tcpdump to see if
it is there
or not)
BTW: The program is under /usr/sbin and needs
root permissions
to be executed

So I strongly suggest to install tcpdump to see what is going
on, on the
network interface (especially on port 123 since this is the ntp port)
An other help could be to check /var/adm/messages
to see if
there is any hint why ntp isn't working properly

Cheers,
Simon

P.S. Sorry for the guessing all the time but it's difficult to give
advice via email.
I have tons of idea where the problems could be
located but to
mention all that I would need to write a book ;-)

-----Original Message-----
From: redhat-list-bounces@xxxxxxxxxx
[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of
Andrew.Bridgeman@xxxxxxxxxxxxxx
Sent: Tuesday, April 21, 2009 11:31 AM
To: General Red Hat Linux discussion list
Subject: RE: Problem with NTP.



Hello Simon,
When I run the ntpq -p server1
command I get an
"timeout, nothing received" so I tried the same command on 5
other machines
that are currently working fine and I get the same error so I
am unsure why
that is. The tcpdump command is showing no such file or
directory, are you
sure the syntax is correct?

Regards

Andrew Bridgeman





"Reber, Simon"

<simon.reber@roch

e.com>
To
Sent by: "General Red Hat Linux
discussion
redhat-list-bounc list"
<redhat-list@xxxxxxxxxx>
es@xxxxxxxxxx
cc



Subject
21/04/2009 10:19 RE: Problem with NTP.





Please respond to

General Red Hat

Linux discussion

list

<redhat-list@redh

at.com>









Well as the configuration does work on other hosts, we don't going to
focus any further on this.
But what's about the output of ntpq -p <ntp
source server>
In your example like: ntpq -p Server1

What does tcpdump telling you:
Run # tcpdump -i <intergace> -vvv port 123
Is there any activity reported?

Cheers,
Simon

-----Original Message-----
From: redhat-list-bounces@xxxxxxxxxx
[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of
Andrew.Bridgeman@xxxxxxxxxxxxxx
Sent: Tuesday, April 21, 2009 11:13 AM
To: General Red Hat Linux discussion list
Subject: RE: Problem with NTP.




Thanks for the reply Simon. Here is the ntpq and ntp.conf info.

remote refid st t when poll reach
delay offset
jitter
===============================================================
===============
Server1 Server2 4 u 9 64 77 18.104 -1193.4
3.107
Server2 Server 3 3 u
5
64 77 19.688 -1188.2 1.623


restrict default noquery nomodify
restrict 127.0.0.1
restrict Server1 mask 255.255.255.255 nomodify notrap noquery
restrict Server2 mask 255.255.255.0 nomodify notrap
server Server1 minpoll 4 maxpoll 6
server Server2 minpoll 4 maxpoll 6
driftfile /var/lib/ntp/drift
logfile /var/log/ntp.log

Remember I use this config for numerous other machines, it is
just this one
I
have an issue with. Any thoughts on possible solutions would be much
appreciated.

FYI

When I run ntpq -p on all of our other Linux machines it shows
as below.

remote refid st t when poll reach
delay offset
jitter
===============================================================
===============
+Server1 Server2 4 u 2 64 377
18.104 -12.428
8.107
*server2 Server 3 3 u
58
64 377 19.688 -0.482 10.623

Regards

Andrew Bridgeman






"Reber, Simon"

<simon.reber@roch

e.com>
To
Sent by: "General Red Hat Linux
discussion
redhat-list-bounc list"
<redhat-list@xxxxxxxxxx>
es@xxxxxxxxxx
cc



Subject
21/04/2009 09:55 RE: Problem with NTP.





Please respond to

General Red Hat

Linux discussion

list

<redhat-list@redh

at.com>









Well the root cause of this issue could be located on various places.
What I can suggest to try is run # ntpq -p <ntp
source server>
<ntp source server> means the server which you
are trying to
synchronize with

If the connection is refused than you know that
you have a
permissions problem somewhere.

An other option is to show the output of ntpq -p and
/etc/ntp.conf
Please make servernames and IP addresses
anonymous.

Cheers,
Simon

-----Original Message-----
From: redhat-list-bounces@xxxxxxxxxx
[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of
Andrew.Bridgeman@xxxxxxxxxxxxxx
Sent: Tuesday, April 21, 2009 10:44 AM
To: redhat-list@xxxxxxxxxx
Subject: Problem with NTP.


I have a new Redhat version 4 server that was built last
week. I have
edited the /etc/ntp.conf and made sure all the entries in the folder
/etc/ntp are the same as all the other Linux machines we have
onsite. It
seems to find time sources as when I use ntpq -p it comes up
with the name
and IP Addresses but I just cannot get it too sync i.e. has a
* or + next
to server IP Addresses. I have pretty much been through the
config on the
machine and the only two things I can see that are different
is that it is
using itself for NIS as it is the NIS master and also in the
/etc/hosts.equiv file it has individual entries not +@trusted
like all the
other machines. I do not think these differences are having an
impact on
NTP not synchronising but just thought I would mention them anyway.

Does anyone know what I can try to solve this issue as the
time on the
server needs to be the same as all the other machines.

Any help would be much appreciated.

Regards

Andrew Bridgeman

*************************************************************
*********
This transmission is confidential and must not be used or
disclosed by
anyone other than the intended recipient. Neither Tata Steel
Europe Limited
nor
any of its subsidiaries can accept any responsibility for any use or
misuse of the transmission by anyone.

For address and company registration details of certain entities
within the Corus group of companies, please visit
http://www.corusgroup.com/entities

*************************************************************
*********

--
redhat-list mailing list
unsubscribe
mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


*************************************************************
*********
This transmission is confidential and must not be used or
disclosed by
anyone other than the intended recipient. Neither Tata Steel
Europe Limited
nor
any of its subsidiaries can accept any responsibility for any use or
misuse of the transmission by anyone.

For address and company registration details of certain entities
within the Corus group of companies, please visit
http://www.corusgroup.com/entities

*************************************************************
*********

--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


**********************************************************************
This transmission is confidential and must not be used or disclosed by
anyone other than the intended recipient. Neither Tata Steel
Europe Limited
nor
any of its subsidiaries can accept any responsibility for any use or
misuse of the transmission by anyone.

For address and company registration details of certain entities
within the Corus group of companies, please visit
http://www.corusgroup.com/entities

**********************************************************************

--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


**********************************************************************
This transmission is confidential and must not be used or disclosed by
anyone other than the intended recipient. Neither Tata Steel
Europe Limited
nor
any of its subsidiaries can accept any responsibility for any use or
misuse of the transmission by anyone.

For address and company registration details of certain entities
within the Corus group of companies, please visit
http://www.corusgroup.com/entities

**********************************************************************

--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list


**********************************************************************
This transmission is confidential and must not be used or disclosed by
anyone other than the intended recipient. Neither Tata Steel Europe Limited
nor
any of its subsidiaries can accept any responsibility for any use or
misuse of the transmission by anyone.

For address and company registration details of certain entities
within the Corus group of companies, please visit
http://www.corusgroup.com/entities

**********************************************************************

--
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list



Relevant Pages

  • RE: Problem with NTP.
    ... what I don't get now is the point that you're running tcpdump on ... server can be found for synchronization is usually does a fallback to ... Yes we are using DHCP service on this machine with bond0. ... from dynamic client and no dynamic leases ...
    (RedHat)
  • RE: Problem with NTP.
    ... -> Maybe also check your ntp version ... you could also try adding a server as source ... Originator Timestamp: 3449307002.785917878 (2009/04/21 ... from dynamic client and no dynamic leases ...
    (RedHat)
  • RE: Problem with NTP.
    ... be able to run the tcpdump command. ... from dynamic client and no dynamic leases ... The "timeout" is coming obviously from the ntp settings set on server1 ... But what's about the output of ntpq -p <ntp source server> ...
    (RedHat)
  • RE: Problem with NTP.
    ... In the ntp.conf the server line is ... what I don't get now is the point that you're running tcpdump on ... Subject: Problem with NTP. ... from dynamic client and no dynamic leases ...
    (RedHat)
  • RE: Problem with NTP.
    ... To make a try run with tcpdump, ... you the entire network traffic from this server. ... Subject: Problem with NTP. ... from dynamic client and no dynamic leases ...
    (RedHat)