Home > General Development > Live Kernel Patches with KspliceLive Kernel Patches with Ksplice David Adams 2010-08-06 General Development 7 CommentsKsplice applies kernel patches on-the-fly – no reboot required — in a fraction of a second. Here’s a hands-on guide to performing painless system updates. Learn how to patch a live kernel and give reboots the boot.About The Author David AdamsFollow me on Twitter @david_adams 7 Comments 2010-08-07 5:14 pm shotsmanQuoteThe authors of Ksplice provide a client application customized for your distro. You can keep your kernel up to date for a nominal fee of less than USD$5 per system per month.Hmmm. A reboot is an awful lot cheaper.We reboot our servers once a month or so anyay so what is this going to give us beyond what we already have?Why do we do this? Well, doing this, we test our DR procedures every month. We fail over from one DataCentre to another. One day later we have a patch/upgrade window. All nice and controlled.Don’t get me wrong, Ksplice is a nice idea and there may be times when I would want to patch this way.However in the world of FOSS I am sure that many will see the charges for a client to manage it as nothing more than a Red rag to a bull. This is not a support charge but a usage charge. These are two very different things IMHO.60+ Servers @5$/month=>$3600 per year just to use something that we don’t really need.I’m sure that not far away, there will be a ‘free to use’ client coming along. Then we might look at it. 2010-08-07 8:47 pm BeresfordFree for Ubuntu Desktops and Fedora 13 if you want to try it out.http://www.ksplice.com/pricingEdited 2010-08-07 20:47 UTC 2010-08-07 9:44 pm JMcCarthyYou don’t actually need to pay $5 to use Ksplice, it’s free software in both sense of the term (GPL). The $5 is for their automagic service, which grabs and applies the necessary updates for you. 2010-08-08 6:50 am shotsmanWhich is why the last line of my post is important.We discussed this in our team yesterday during one of our monthly system update operations.The general concensus is that ksplice would be of use to systems that never had any planned downtime.Ours do. We failover to the DR site and run that as the main for a month before failing back.The charge for a client to find the patches was met with derision. Nothing gets onto our production servers without going through proper testing. So far in 4+ years (before my time at the site) we have not had to apply an emergency patch to the kernel.Therefore in our particular case, We don’t need no pay for use client.It might be free for F13 or Ubuntu xx.yy but all of our systems are RHEL or CentOS. For these we have to pay.Sorry. not interested in this. 2010-08-07 8:10 pm iaefaiSounds like a good way of causing instability. 2010-08-09 12:07 am ZifreSounds like a good way of causing instability.I have tried Ksplice several times before. It’s an awesome concept, and generally works. However, I have had it crash the kernel once. I suppose something else could have caused it, but it happened right after I used Ksplice. 2010-08-08 9:52 am Beket_From a technological point of view it is admirable how (well) it works.