Network Time Protocol (NTP)

NTP will be used to keep the clocks syncronized between the VM Server and the VM Guests.

Configure Timezone Settings

<html>You need to make sure your machine is using the correct timezone settings, so that it will properly adjust the time based on the current timezone configuration. At the prompt type:</html>

sudo /usr/bin/tzselect

<html>You will then be need to answer a series of questions. <ul> <li>First, you will select your continent.</html>

Please identify a location so that time zone rules can be set correctly.
Please select a continent or ocean.
 1) Africa
 2) Americas
 3) Antarctica
 4) Arctic Ocean
 5) Asia
 6) Atlantic Ocean
 7) Australia
 8) Europe
 9) Indian Ocean
10) Pacific Ocean
11) none - I want to specify the time zone using the Posix TZ format.
#? 2

<html>I used 2 for “Americas”.</li> <li>Second, you will select your country.</html>

Please select a country.
 1) Anguilla                 27) Honduras
 2) Antigua & Barbuda        28) Jamaica
 3) Argentina                29) Martinique
 4) Aruba                    30) Mexico
 5) Bahamas                  31) Montserrat
 6) Barbados                 32) Netherlands Antilles
 7) Belize                   33) Nicaragua
 8) Bolivia                  34) Panama
 9) Brazil                   35) Paraguay
10) Canada                   36) Peru
11) Cayman Islands           37) Puerto Rico
12) Chile                    38) St Barthelemy
13) Colombia                 39) St Kitts & Nevis
14) Costa Rica               40) St Lucia
15) Cuba                     41) St Martin (French part)
16) Dominica                 42) St Pierre & Miquelon
17) Dominican Republic       43) St Vincent
18) Ecuador                  44) Suriname
19) El Salvador              45) Trinidad & Tobago
20) French Guiana            46) Turks & Caicos Is
21) Greenland                47) United States
22) Grenada                  48) Uruguay
23) Guadeloupe               49) Venezuela
24) Guatemala                50) Virgin Islands (UK)
25) Guyana                   51) Virgin Islands (US)
26) Haiti
#? 47

<html>I used 47 for “United States”.</li> <li>Third, you will select your time region; if applicable.</html>

Please select one of the following time zone regions.
 1) Eastern Time
 2) Eastern Time - Michigan - most locations
 3) Eastern Time - Kentucky - Louisville area
 4) Eastern Time - Kentucky - Wayne County
 5) Eastern Time - Indiana - most locations
 6) Eastern Time - Indiana - Daviess, Dubois, Knox & Martin Counties
 7) Eastern Time - Indiana - Pulaski County
 8) Eastern Time - Indiana - Crawford County
 9) Eastern Time - Indiana - Pike County
10) Eastern Time - Indiana - Switzerland County
11) Central Time
12) Central Time - Indiana - Perry County
13) Central Time - Indiana - Starke County
14) Central Time - Michigan - Dickinson, Gogebic, Iron & Menominee Counties
15) Central Time - North Dakota - Oliver County
16) Central Time - North Dakota - Morton County (except Mandan area)
17) Mountain Time
18) Mountain Time - south Idaho & east Oregon
19) Mountain Time - Navajo
20) Mountain Standard Time - Arizona
21) Pacific Time
22) Alaska Time
23) Alaska Time - Alaska panhandle
24) Alaska Time - Alaska panhandle neck
25) Alaska Time - west Alaska
26) Aleutian Islands
27) Hawaii
#? 1

<html>I used 1 for “Eastern Time”</li> <li>Last, you will be asked to review your information for correctness:</html>

The following information has been given:

        United States
        Eastern Time

Therefore TZ='America/New_York' will be used.
Local time is now:      Thu May 20 12:36:14 EDT 2010.
Universal Time is now:  Thu May 20 16:36:14 UTC 2010.
Is the above information OK?
1) Yes
2) No
#? 1

<html>I entered 1 because it was correct.</li></ul></html>

Install the NTP Package

To install NTP, first lets make sure that our sources list is current, and all the latest package updates are intalled, and then install the package ntp.

sudo sh -c "aptitude update && aptitude safe-upgrade -y && aptitude install -y ntp"

NTP should now be installed and running.

Configuring a NTP Server

<html>The VM Server, vmserver03, will be acting as a NTP server to the VM Guests. You need to edit /etc/ntp.conf using the editor of your choice to tailor things to your needs.</html>

sudo vim /etc/ntp.conf

<html>The ntp.conf file on our server is as follows:</html>

# /etc/ntp.conf
# Local clock oscillation file
driftfile /var/lib/ntp/ntp.drift
 
# Allow statistics to be logged.
statsdir /var/log/ntpstats/
 
# Logging configuration
statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable
 
# Access control configuration
restrict default kod nomodify notrap nopeer noquery # Deny everybody by default
restrict 127.0.0.1                                  # Allow unrestricted access to self
restrict 10.80.3.0 mask 255.255.255.0 nomodify      # Serve time to local network
 
# NTP servers to syncronise with
server juicebox.lair.lan
 
# Allow localhost to serve as a back-up time server
server 127.127.1.0
fudge 127.127.1.0 stratum 10

<html>Now restart the NTP service to implement the changes.</html>

sudo /etc/init.d/ntp restart

Configuring a NTP Client on a Virtual Machine

<html>Again, you need to edit /etc/ntp.conf using the editor of your choice to tailor things to your needs.</html>

sudo vim /etc/ntp.conf

<html>The ntp.conf file on our client is as follows:</html>

# /etc/ntp.conf
 
# Disable the panic threshold to allow irregular clock offsets
tinker panic 0 
 
# Local clock oscillation file
driftfile /var/lib/ntp/ntp.drift
 
# Allow statistics to be logged.
statsdir /var/log/ntpstats/
 
# Logging configuration
statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable
 
# Access control configuration
restrict default kod nomodify notrap nopeer noquery # Deny everybody by default
restrict 127.0.0.1                                  # Allow unrestricted access to self
 
# NTP servers to syncronise with
server vmserver03.student.lab

<html> The main difference between our client and our server ntp.conf files is that the client file does not have a restrict directive that allows it to serve time to other systems. It also does not look to itself as a server. We need to do some additional configuration before we restart the NTP service to apply the changes on our virtual macines.</html>

Special Settings for Virtual Machines

<html>Because the NTP clients for the purposes of this portfolio will be used on Xen Virtual Machines, a few special configuration enhancements need to be made. The first, is the line tinker panic 0 from our client version of the ntp.conf. This allows the NTP client to update from the NTP server, regardless of differences in current system time – there are instances where the VM will begin adjusting it's clock automatically due to various system errors. The other requirement is to create a step-tinkers file and place it in /etc/ntp directory. (You may need to create this directory as it is not created by default as part of the installation process for NTP.)</html>

sudo sh -c "mkdir /etc/ntp && vim /etc/ntp/step-tinkers"

# /etc/ntp/step-tinkers
vmserver03.student.lab

<html>Restart the NTP service to implement the changes.</html>

sudo /etc/init.d/ntp restart

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