Re: [CentOS] upgrade question. - when to reboot
On 1/15/09, Kenneth Burgener kenn...@mail1.ttak.org wrote: On 1/9/2009 9:49 AM, Robert Nichols wrote: If a hard reboot is what you are attempting to avoid, with 'kexec' even the Linux kernel can be reloaded without a hardware reset. This is convenient if you want to avoid the long system reset time. Kexec is a patch to the Linux kernel that allows you to boot directly to a new kernel from the currently running one. In the boot sequence described above, kexec skips the entire bootloader stage (the first part) and directly jumps into the kernel that we want to boot to. There is no hardware reset, no firmware operation, and no bootloader involved. The weakest link in the boot sequence -- that is, the firmware -- is completely avoided. The big gain from this feature is that system reboots are now extremely fast. For enterprise-class systems, kexec drastically reduces reboot-related system downtime. For kernel and system software developers, kexec helps you quickly reboot your system during development or testing efforts without having to go through the costly firmware stage every time. [1] if you really have to have as perfect an uptime as possible then you can actually patch a running kernel using ksplice http://www.ksplice.com/ should only be used for critical security updates but useful nonetheless mike ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] upgrade question. - when to reboot
Michael Simpson wrote: if you really have to have as perfect an uptime as possible then you can actually patch a running kernel using ksplice http://www.ksplice.com/ should only be used for critical security updates but useful nonetheless mike ___ Its not that I want a perfect uptime, I just want to make sure I reboot when needed and not reboot when it is not necessary. Thank you all for your input. Brian. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] upgrade question. - when to reboot
On 1/9/2009 9:49 AM, Robert Nichols wrote: Brian wrote: Is there a list of packages that after update require a reboot, other then kernel? For updates other than the kernel, there is almost always an answer short of a full reboot. But, finding that answer and being 100% certain that it is a complete answer can be a challenge, and is, say, bringing the system down to single-user mode momentarily all that much better than simply rebooting? If a hard reboot is what you are attempting to avoid, with 'kexec' even the Linux kernel can be reloaded without a hardware reset. This is convenient if you want to avoid the long system reset time. Kexec is a patch to the Linux kernel that allows you to boot directly to a new kernel from the currently running one. In the boot sequence described above, kexec skips the entire bootloader stage (the first part) and directly jumps into the kernel that we want to boot to. There is no hardware reset, no firmware operation, and no bootloader involved. The weakest link in the boot sequence -- that is, the firmware -- is completely avoided. The big gain from this feature is that system reboots are now extremely fast. For enterprise-class systems, kexec drastically reduces reboot-related system downtime. For kernel and system software developers, kexec helps you quickly reboot your system during development or testing efforts without having to go through the costly firmware stage every time. [1] Kenneth [1] http://www.ibm.com/developerworks/linux/library/l-kexec.html ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
