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Running yum --security check-update returns this message:

Security: kernel-3.x.x-x.63 is an installed security update 
Security: kernel-3.x.x-x.29 is the currently running version

I already ran the yum security update on the kernel, but it looks like it didn't change the version running on the system. What needs to be done to make it run the new kernel? Are there any concerns about why it didn't change during the installation process? The yum log just shows installed for the new kernel no error messages.

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This might be an idiot question, but have you rebooted since yum updated the kernel? The normal way to run a new kernel is to reboot into it. – MadHatter Oct 10 '12 at 15:35
up vote 1 down vote accepted

I wouldn't dream of contradicting you, but I've never known the version of the running kernel change merely by installing a higher-numbered version. In my experience, the normal way to run a newer kernel is to reboot into it.

There was once something called the two-kernel monty, if memory serves, that allowed a newer version kernel to usurp the identity of a running one, and take the machine over, but it required a lot of preparation and I never heard tell that it was reliable; there appears to be ksplice to do it these days. But I'd also assume you'd know if you were setup for any of these technologies already.

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Makes sense, always wondered how patching real time was possible. Guess it doesn't do that. – JMC Oct 10 '12 at 15:53

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