V Sun, 26 Feb 2012 02:50:46 +0700 Pandu Poluan <pa...@poluan.info> napsáno:
> On Feb 26, 2012 2:05 AM, "Robert David" > <robert.david.pub...@gmail.com> wrote: > > > > V Sat, 25 Feb 2012 10:32:20 -0800 > > Grant <emailgr...@gmail.com> napsáno: > > > > > >> >> I need to test a kernel config change on a remote system. > > > >> >> Is there a safe way to do this? The fallback thing in grub > > > >> >> has never worked for me. When does that ever work? > > > >> > > > > >> > > > > >> > You can press ESC in the Grub screen and it will take you to > > > >> > text-only mode. There, you select an entry, press "e" and > > > >> > edit it. Press ENTER when you're finished, and then press > > > >> > "b" to boot your modified entry. > > > >> > > > > >> > That way, you can boot whatever kernel you want if the > > > >> > current one doesn't work. > > > >> > > > >> I can't do that remotely though. I'm probably asking for > > > >> something that doesn't exist. > > > >> > > > >> - Grant > > > >> > > > > > > > > Don't do that if you don't have some tool like KVM, or other > > > > remote management of the server. Or if it is available in the > > > > data center, just call them and order this service for the time > > > > you need to do updates. > > > > > > > > This is why I don't use gentoo on servers any more, just because > > > > I rather stay safe than sorry. > > > > > > How is another distro different in this situation? > > > > > > - Grant > > > > Just because when using distros like Centos/RHEL or Debian stable, > > you have very little chance that the kernel released will fail. Due > > to extensive testing, user base and update policy. And major kernel > > update you done only once in few years and the transition is tested > > before release done (though you are supposed to test yourself to be > > safe). > > > > This is not saying that gentoo is bad, I'm very big fan of gentoo. > > But you have to concern where it use and where not. > > > > Robert. > > > > Anecdotal, but... > > I once had an Ubuntu VM that can't shutdown after a kernel update. > First boot after update went well, but when I rebooted it again, it > pegged its vCPUs at 100% before I ordered the Xen hypervisor to put > it out of its misery. I don't want to start flame, but ubuntu was never a system for server for me. It may be good for desktop, but not server. For me ubuntu is too up-to-date to be a good server distro, even the LTS is not something well done, maybe in version x.x.3-4 of LTS it s reasonable to put on server, but it will soon end with support. So nothing for me. > > The bug was apparently in the portion of the kernel running in the > primary CPU that's responsible for shutting down the other CPUs > before cutting the power. And IIRC, this bug affects all > multi-processor configuration. > > So, as you can see, binary distros can still fuck up royal time. Not > to mention that if you have an exotic configuration, support for your > configuration might not be built into the kernel by the distro. > This is true, but you cannot compare countless options that gentoo can be configured with few options that binary distro is capable and thus more probably tested before. > Somehow I believe people deploying Gentoo servers will be much more > careful... Agree. But real word is not so ideal. I got situations where I need upgrade basic gentoo server to more special virtualized environment. Just a customer wanted that. This consist about changing net to bridge, add/update kernel modules, etc. I ended with bricked server after a long checks etc, so I have to check the server physicaly. I did another thing in debian remotely within a half hour. This also implies that I'm not so good admin, but things happen not so good as you expect every time. I still use gentoo on my notebook and work computer, or specialized project where it benefits. But all the servers are migrated to debian or centos. I just don't have so much time to play. Robert. > > Rgds,
