Linux

No more rebooting. Period.

Imagine updating your PC's kernel and not having to reboot. That dream has become a reality with the Linux operating system thanks to KSplice. Jack Wallen shows you how you can have as close to 100-percent uptime as possible.

There's a new technology in town for the Linux operating system called Ksplice Uptrack. With this system in place you can now update your system - even the kernel - without a single reboot. Let me say that again - EVEN THE KERNEL! What exactly does that mean? You know all of those promises made by other OS vendors who claim a near 100 percent uptime with their machines? What happens to those machines when you install a service pack that does anything to the kernel? Time for a reboot. (Actually it doesn't even require a kernel-level update to require a reboot.)

We all know (or should know) that the Linux operating system is an amazingly stable OS. Uptime numbers can be staggering in comparison to other OSs. I can go months on end without a single reboot - only to have to do so when the kernel was touched by an upgrade. And now that the ante has been seriously upped, because even those kernel updates won't mean a reboot.

Zero reboots. Period.

But how does it work? Actually it's quite simple. Follow these steps:

  1. Install Uptrack from Ksplice.
  2. Use the Ksplice Uptrack GUI to handle the updates for your kernel.
  3. End of story. It's the new world order - get used to it.

Okay, let's take a closer look at how this works. If you go to the Ksplice How It Works page you will find download files for:

  • Ubuntu 9.10
  • Ubuntu 9.04

As well, a trial server for the following Enterprise Linux distributions:

  • Red Hat Enterprise Linux 4/5
  • CentOS 4/5
  • Debian 4.0/5.0
  • SuSE 10/11
  • Ubuntu 8.04

If you're using Ubuntu, download the correct version  for your release and let GDebi handle the installation for you. During the installation you will have to agree to a license, after which the installation will complete.

Figure A

Once complete, KSplice Uptrack will open to inform you if there are any updates available for your system. Figure A shows KSplice with an update available.

All you need to do is click the Install All Updates button to apply any available kernel updates.

Once this process is complete you can close the KSplice Uptrack Manager and go about your business. No rebooting need apply.

There is also a panel icon for the application that will notify you if any updates are available.

Which updates?

You may notice that KSplice does not handle ALL updates to your kernel. There is a reason for that. Approximately 88% of kernel updates do not require any custom code in order to work with KSplice. The remaining 12% can be altered with 1-12 lines of code in order to work. With that 100% of kernel updates can be done without a reboot. Here's how KSplice works:

  1. A bug or security hole is discovered in the Linux kernel.
  2. Developers fix said bug or hole.
  3. KSplice software analyzes the fix and creates an update image which can be implemented without reboot.
  4. KSplice Uptrack Manager picks up fix and applies it to your computer.

During the process your service will be interrupted for 0.7 milliseconds. That's it. Imagine having as near to 100 percent uptime as possible (minus the .7 milliseconds necessary to apply any KSplice fix) on your servers or desktops? Well...it's now possible.

I've used KSplice on my Ubuntu systems and have yet to have to reboot a single machine. Now my only concern is Mother Nature and the great power outages (that can be averted thanks to UPSs and generators.)

Final thoughts

I'm not going to stick my finger in the air and proclaim, "We're number one" here. But I can't imagine the competition being able to match a feature like this in the near future. Linux has been handed what could be the Holy Grail of uptime. Along with the amazing improvements the distributions have made in the last couple of years, Linux is on the cusp of something very, very special.

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About

Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website getjackd.net.

18 comments
jackie40d
jackie40d

I have it installed now and it does a lot of the usual re boot stuff taken out of my time Like i ma at a library up dating a computer for some one and the re booting is not there ( using Ubuntu 9.10 now )

pasivemanagement
pasivemanagement

Hi, Ksplice is in Reposotories, but use downloaded version, then it works at least. Janis

techrep
techrep

Great! But why-oh-why use a GUI? Uptime is mainly a concern for servers. My servers all run without a GUI. If this depends on a GUI, count me out...

theguru1995
theguru1995

Great, We do the SAME in SOLARIS, our servers have above 650 days uptime, some even more...take that.

ltjackal
ltjackal

Nothing is impossible, yet it's not probable :) I already have and using GNU/Linux ... what to pick, what to pick :)

Photogenic Memory
Photogenic Memory

0.7 milliseconds means the system was unavailable for well........0.7 seconds. That means the system isn't up 100%. However, who is going to notice. I wonder if this is a ripe moment for a buffer-underrun leading to a disguised binary to make it's way into the OS and escalate some privileges. Nah, no one is thinking of that. LOL!

frank.domnick
frank.domnick

I have some more questions to ask: Why does Ksplice give away only the Ubuntu versions for free? Why do I have to sign up before being told the price for the Enterprise Linux versions? What a strange way of treating potential customers... Apart from this having an uptime of close to 100% sounds too good to be true and I doubt that there are enough companies around that are willing to pay for Linux-related software of this kind. Those of them with great demands for uninterruted operations will have some kind of a virtual infrastructure or clustered servers and the others will accept one or two re-boots per year.

kb1493
kb1493

First of all, 100% uninterrupted uptime of a system is impossible. You don't have to be a sysadmin to know this as there are some risks to such uptime that are plainly obvious -- such as a power outage (and a UPS can only last so long before it must prompt the systems connected to it to shut down). But I'm rather skeptical of their claims at this time, partially because of how new this whole thing is -- you can always expect some air of skepticism around new technologies. The paper describing KSplice was first published in April 2009, and I don't see it being widely adopted until it has become more proven, especially in intense enterprise environments (such as large corporations, hospitals, the like). They also need to gather some hard statistics that they can publish periodically on their web site showing how well their system does over time under pressure.

jlwallen
jlwallen

Actually, with the help of KSplice, 100% of kernel updates can be done without a reboot. The 88 % is attributed to the amount of kernel code that can be applied without any adjustments by the KSplice developers.

MrWoodleigh
MrWoodleigh

I hope this is a typo: Only approximately 88% of kernel updates require a reboot.

packetracer
packetracer

All of Solaris, HP-UX and AIX (latest versions) do this already. Without having to sign up for a special service.

Cisco-SA
Cisco-SA

0.7mS is 0.0007 seconds. This means that any user request or service request is held off for 0.7mS; it is not denied, it is postponed. So yes, the up-time stays at 100%. Using your analogy, if a ping comes into your box and it delays response by 1mS then you must re-start your up-time. P.S. I have saved 11,835 jobs today.

Pringles86
Pringles86

"0.7 milliseconds means the system was unavailable for well........0.7 seconds" Wrong, 0.7 milliseconds = 0.0007 seconds. He also says a couple times it is not 100% uptime: "Jack Wallen shows you how you can have as close to 100-percent uptime as possible." "Imagine having as near to 100 percent uptime as possible" So, I'm not sure how the article is misleading...

theguru1995
theguru1995

If we are going to claim open source, ok, but our pals at KSPLICE are only patching the kernel, like when we brand, or edit the running bin of the kernel, call it what u want. It can only be done when U know for sure, how to splice the patch/bin into a runnig kernel... u need to know source, and a whole bunch of other stuff... this is for a vanilla kernel... uptime, I know uptime :-)

Mark Johnson
Mark Johnson

Let me state up front that I am not a kernel expert, but unless the kernel is completely stateless, this app must have the effect of patching executing code and possibly rebuilding the associated in-memory data structures. The resulting code has kernel priviliges by definition. All automatic without my knowledge or approval? It sounds like it has the potential to be my worst security nightmare

ps.techrep
ps.techrep

I think that this could be a valuable addition to our systems, but this looks like a critical component. For critical components, generally I wait for them to become part of the distribution, because I don't like to be one of the pioneers found with arrows sticking out of their backs. How widely has this software been tested by the Linux community? What has the Ubuntu user experience been in the 6 months that this has been out?

craiglarry
craiglarry

if you have ubuntu 9.10 you don't have to go third party to get this. It's in the repositories. A couple of clicks and it's done and fully vetted by the people who write the code.

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