WTF Is A Step Ticker? – Step Tickers. and Why They Matter

by bunchc on May 14, 2009

What is a “Step Ticker”

You know, it’s one of those little pedometer things you strap onto your hip and tracks how far you’ve walked. Ok, so it’s not that. At least not within the context of servers & virtualization. So what IS it? It’s a horribly named NTP (network time protocol) concept. Yup. That’s it. You were expecting at least two other paragraphs, no?

What does it do?

Hate to disappoint, this paragraph is going to be short too. A Step Ticker is basically a way to tell the NTP daemon to check a server or two, and correct time on startup, rather than relying on the time that was restored from the hardware.

This is meaningful, because often the hardware time has drifted. If you are running applications that are exceedingly time sensitive, like virtualization, you’ll of course want accurate time. So setting up Step Tickers is a “Good Idea”. So how do we do that?

Setting Up Step Tickers

I’ll show you how to do this on a single host, as well, that’s easy, and I’m lazy. To deploy in mass, you’ll likely want this as part of your kickstart process. If you don’t have automated builds, shame on you, but you should have it as part of your QC process then. As for scripting the change out to each host, that is best left to you, the reader (but can be done in PoSH with plink).

Enough rambling, open /etc/ntp/step-tickers and add some lines that look like this

0.vmware.pool.ntp.org
1.vmware.pool.ntp.org
2.vmware.pool.ntp.org

From here, save the file and restart ntp (service ntpd restart).

Questions? Drop a line in the comments.

Sources: Tripwire KB, VMware KB, and some random UseNet/Mailing list  post about ntpd.

{ 11 comments }

jeff June 3, 2009 at 12:04 pm

I'm not sure each line should have 'server' at the beginning.

According to: Installing and Configuring NTP on VMware ESX Server (http://kb.vmware.com/selfservice/microsites/sea...)

Edit /etc/ntp/step-tickers so that the file looks like the following example:

0.vmware.pool.ntp.org
1.vmware.pool.ntp.org
2.vmware.pool.ntp.org

jeff June 3, 2009 at 12:35 pm

Looks like the tripwirekb article needs to be corrected to conform to the vmware kb.

professionalvmware June 3, 2009 at 2:39 pm

Good catch. Post has been updated, and I've pinged Tripwire.

dildotoys June 22, 2009 at 8:31 am

Me and my buddy had a discussion about this and its importance the other night, and we even raised a bet over it. He was leaning on its value while I debated him otherwise. However, upon reading this post of yours, I must admit that I stand corrected. Guess I owe my buddy a six pack. :( Nevertheless, I got to know more about it, even though I somewhat got kicked in the balls over it. lol

Freestyle June 24, 2009 at 3:59 am

Thanks for making things clear, I totally appreciate it!

Freestyle June 24, 2009 at 8:59 am

Thanks for making things clear, I totally appreciate it!

tiffany1111 December 30, 2009 at 9:18 am
Aidan May 30, 2010 at 10:22 pm

> I'm not sure each line should have 'server' at the beginning.

It works with or without. I suspect that the server directive is simply ignored.

Matt July 31, 2010 at 2:59 pm

CentOS and RHEL have this by default. Any ideas why it's missing from Ubuntu?

professionalvmware August 2, 2010 at 10:13 am

Hey Matt,

Looking into this as I’m not quite sure either. What verion of Ubuntu are
you running?

professionalvmware August 2, 2010 at 5:13 am

Hey Matt,

Looking into this as I'm not quite sure either. What verion of Ubuntu are
you running?

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