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I have a small network with populated with 4 or 5 machines all on the same router. At this time I'm developing software so the router is connected to the internet but when deployed this will be a standalone LAN. When deployed only one machine will have windowing (gnome), the others will be headless, boot to command line, and start an application automatically but right now all are booting to GNOME.

There is also a GPS enabled NTP Server appliance (not a computer) on the LAN.

All the IP Addresses are fixed.

How should this be set up? I'm asking because I think I see some problems. For instance the resolv.conf files are identical and I'm told that Gnome runs some kind of a nameserver.


All the host files are:   localhost   loopback

# hpnotebook is the local machine   hpnotebook master   orange   blue    vis   maroon  mir   green   tir   nts ntpserver

When deployed the computer "orange" will act as the master and run Gnome with a monitor etc. and "hpnotebook" will not be present as it's only for development and debugging.

Samba is running.

I am doubting that the LAN is configured correctly because ntpq shows that the clocks are not being set as accurately as they should be and, if I understand the output correctly, it is telling me that the ntp serve appliance is not on the local LAN, but it is.

Using tcpdump from hpnotebook I see traffic that I don't understand.

sudo /usr/sbin/tcpdump | grep nts
14:16:05.467044 ARP, Request who-has nts tell hpnotebook, length 28
14:16:05.467214 ARP, Reply nts is-at 00:20:4a:bd:af:8a (oui Unknown), length 46
14:17:09.462100 IP hpnotebook.ntp > nts.ntp: NTPv4, Client, length 48
14:17:09.501020 IP nts.ntp > hpnotebook.ntp: NTPv4, Server, length 48
14:17:14.475039 ARP, Request who-has nts tell hpnotebook, length 28
14:17:14.475255 ARP, Reply nts is-at 00:20:4a:bd:af:8a (oui Unknown), length 46
14:17:23.664651 ARP, Request who-has maroon tell nts, length 46
14:17:27.107981 ARP, Request who-has nts tell nts, length 46
14:18:15.462146 IP hpnotebook.ntp > nts.ntp: NTPv4, Client, length 48
14:18:15.501096 IP nts.ntp > hpnotebook.ntp: NTPv4, Server, length 48

It looks to me as if hpnotebook and maroon are continually asking what the MAC address of nts (the time server) is. Orange is running but it is not asking hpnotebook.

Shouldn't the mac address of nts be in a table somewhere as part of the LAN setup?

I'm still attempting to learn LINUX and Ubuntu. I've been searching for answers but have not yet found them.

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1 Answer 1

I use the /etc/ntp.conf file to connect to a timeserver in my country. So I replace the default Ubuntu servers with other public time servers from NTP Servers

But at the end of that file, there are also settings for a local network timeserver.

Because your local timeserver has IP, it should broadcast this address. and the clients should get the time from that address

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My NTP serve is not a computer and it can't configured to do this. I must make sure that my LAN is configured to work correctly when only one machine is running Gnome as it appears that Gnome may be acting as a local name server. Then work with NTP. Thanks –  Nate Lockwood Apr 28 '13 at 1:26

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