PDA

View Full Version : NTP via tcp?



Bernd Nachtigall
11-Jan-2013, 11:36
Hi,

is there a way to use the TCP-Protocol insteed of the UDP-Protocol for NTP
in SLES10/SLES11? (I know that TCP is not smart for NTP but the enviroment
use TCP for NTP :-\)

Bye

Bernd

malcolmlewis
11-Jan-2013, 13:29
On Fri 11 Jan 2013 10:36:36 AM CST, Bernd Nachtigall wrote:

Hi,

is there a way to use the TCP-Protocol insteed of the UDP-Protocol for
NTP in SLES10/SLES11? (I know that TCP is not smart for NTP but the
enviroment use TCP for NTP :-\)

Bye

Bernd


Hi
You mean the time service on tcp port 37? You would need to enable time
and the xinetd service.

--
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 22:41, 3 users, load average: 0.00, 0.03, 0.05
CPU Intel® i5 CPU M520@2.40GHz | GPU Intel® Ironlake Mobile

Bernd Nachtigall
11-Jan-2013, 14:26
malcolmlewis wrote:

>

> On Fri 11 Jan 2013 10:36:36 AM CST, Bernd Nachtigall wrote:
>
> Hi,
>
> is there a way to use the TCP-Protocol insteed of the UDP-Protocol for
> NTP in SLES10/SLES11? (I know that TCP is not smart for NTP but the
> enviroment use TCP for NTP :-\)
>
> Bye
>
> Bernd
>
>
> Hi
> You mean the time service on tcp port 37? You would need to enable time
> and the xinetd service.
>

No,
I mean the Network Time Protocol on Port 123.

I assume that timeservice is outdated, isn't it?

Bye

Bernd

malcolmlewis
11-Jan-2013, 15:25
On Fri 11 Jan 2013 01:26:52 PM CST, Bernd Nachtigall wrote:

malcolmlewis wrote:

>

> On Fri 11 Jan 2013 10:36:36 AM CST, Bernd Nachtigall wrote:
>
> Hi,
>
> is there a way to use the TCP-Protocol insteed of the UDP-Protocol for
> NTP in SLES10/SLES11? (I know that TCP is not smart for NTP but the
> enviroment use TCP for NTP :-\)
>
> Bye
>
> Bernd
>
>
> Hi
> You mean the time service on tcp port 37? You would need to enable
> time and the xinetd service.
>

No,
I mean the Network Time Protocol on Port 123.

I assume that timeservice is outdated, isn't it?

Bye

Bernd


Hi
The ntp protocol doesn't/can't use tcp only udp. So the server
you trying to sync to must be either time or daytime?

Maybe your time reference system is just using port tcp/123 maybe a
packet capture from tcpdump or wireshark might identify.

--
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 1 day 0:18, 3 users, load average: 0.10, 0.10, 0.06
CPU Intel® i5 CPU M520@2.40GHz | GPU Intel® Ironlake Mobile

jmozdzen
15-Jan-2013, 14:52
Hi,

is there a way to use the TCP-Protocol insteed of the UDP-Protocol for NTP
in SLES10/SLES11? (I know that TCP is not smart for NTP but the enviroment
use TCP for NTP :-\)

Bye

Bernd

Hi Bernd,

It'd be really interesting to know which "environment" makes use of TCP for NTP, as this violates the RFCs. The latest protocol definition for NTPv4 (RFC 5905) explicitly states in 7.3 that "the NTP packet is a UDP datagram".

Regards,
Jens

Bernd Nachtigall
17-Jan-2013, 09:42
jmozdzen wrote:

(...)
> It'd be really interesting to know which "environment" makes use of TCP
> for NTP, as this violates the RFCs. The latest protocol definition for
> NTPv4 (RFC 5905) explicitly states in 7.3 that "the NTP packet is a UDP
> datagram".
(...)

There was a firewall which has blocked UDP. But now the service partner who
manage this part has corrected the settings. NTP runs fine now :-)

Thx for the RFC number!

Bye

Bernd