VMWare and slow clocks – take 2

2009/01/09

The centos 4.x we are using as platform for the VMWare VMs (yes, I know there is version 5, but we need to be compliant with RHEL 4.x because of the ATG requirements) installs by default the NTP client.

Here is sequence of steps that needs to be performed to enable automatic synchronization of the clocks.
1) make sure the DNS works
cat /etc/resolv.conf

sudo vi /etc/resolv.conf

– check that nameservers point to something meaningfull, e.g.
nameserver 208.67.222.222
nameserver 208.67.220.220
nameserver 192.168.16.1

2) check that you have ntpd installed

cat /etc/ntp.conf

– inspect the content of the file, it is quite well documented

3) make it work in runlevels 2345

/sbin/chkconfig –list | grep ntpd

– this will most likely show “off” for all runlevels

sudo /sbin/chkconfig –level 2345 ntpd on

4) Initial sync

sudo /usr/sbin/ntpdate pool.ntp.org

– do this twice, on second you should get very small difference

5) Start service / restart service

sudo /sbin/service ntpd start

Making this a blog post so that next time I need to do it I can easily find it :-). Maybe somebody else will find it useful as well.

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VMWare and slow clocks

2009/01/04

I have noticed recently that most of our VMWare instances (and we are running decent fleet of them for the ATG Lab as well as internal system) if left without time synchronization, will loose get late quite a bit: some of them as much as hour or more a week.

Unix date command unfortunately belongs to those commands that I am having troubles to remember and everytime I have to use it with parameters, I end up googling for examples …

The following snippet is useful when correcting only time portion:

[tkuser@jci-app ~]$ date
Sat Jan 3 11:28:12 EST 2009

[tkuser@jci-app ~]$ sudo date -s "13:45"
Password:
Sat Jan 3 13:45:00 EST 2009

[tkuser@jci-app ~]$ date
Sat Jan 3 13:45:04 EST 2009

Weird Rogers 3G network error – fixed ?

2009/01/02

Just tried out to switch the iPhone to automatic Date and Time setting with 3G on. The time jumped from 11:31 to 11:30 (my iPhone was about 1 minute too fast) and STAYED THERE.

This could mean that the issue is finally fixed. Can anybody confirm that ?


Excellent free Git tutorial

2009/01/02

Two screencasts, about 80 and 40 minutes long are available at:

http://excess.org/article/2008/07/ogre-git-tutorial/

Courtesy by fellow Ottawan Bert Trojanowski. Really nice job of providing deep enough technical understanding with good illustrative examples.

If you want to get into distributed version control (which is IMHO way to go), check this out.