On Thu, Jul 2, 2015 at 2:43 AM, ken <gebser at mousecar.com> wrote:> On 07/01/2015 05:10 PM, Jonathan Billings wrote: >> >> >>> On Jul 1, 2015, at 12:20, Chris Murphy <lists at colorremedies.com> wrote: >>> >>> My understanding is CentOS doesn't really support dual-boot anyway, >>> whereas Fedora does. >> >> >> Nope. CentOS 5, 6 and 7 all support dual-boot.Considering CentOS 7, at least, doesn't include ntfsprogs, the installation of CentOS can't support shrink or discovery of Windows in order to create a GRUB menu entry for it. That tools exist the user can make this work after installation is not at all what I'd consider "supported".> Since Linux first came out in '92, every distro I've used-- SLS, Slackware, > Redhat, Suse, CentOS, and probably one or two others-- *all* have allowed > dual-boot. The feature is built into grub, and lilo before that. Anyone > who put together a distro which didn't support dual-boot would have to take > the feature out-- rewrite the code (and why do that just to take out a > perfectly functioning feature?)--, else use some other boot loader... e.g., > the Raspberry Pi distros don't support dual-boot AFAIK.Dual boot support has a large number of dependencies, it's not just dependent on GRUB doing the right thing. When ntfsprogs isn't included on installation media, for example, Windows dual boot isn't going to happen at install time, you have to do it manually after installing ntfsprogs. Further, Anaconda (the installer used by RHEL, CentOS, Fedora) does not support enabling all LVs at installation time. Therefore GRUB won't find other Linux installations. So a default CentOS installation followed by a default Fedora installation, or vice versa; or CentOS/Fedora n system which then has n+1 installed, renders the n version unbootable. The user has to fix this post install. I'd hardly call this form of dual boot support, any kind of support whatsoever. https://bugzilla.redhat.com/show_bug.cgi?id=825236 Next, the RHEL/CentOS/Fedora GRUB lacks the rather old patches that SUSE submitted, to bring UEFI Secure Boot to GRUB's chainloader.mod. Therefore it isn't possible to have Secure Boot enabled, and chainload Windows 8 (it fails). So that's broken too. https://bugzilla.redhat.com/show_bug.cgi?id=1170245#c23 Finally, GRUB's grub-mkconfig command doesn't create EFI chainloading entries for OS X. Instead it wrongly assumes Linux is booted in CSM-BIOS mode, and has OS X boot entries designed to do an EFI boot from a BIOS build of GRUB and the result is a kernel panic. For this to work correctly it needs to chainload Apple's OS X bootloader, which is the only reliable way to do this now that they've moved to using their version of a logical volume manager by default, and nothing in the free software world knows how to read that format yet. https://bugzilla.redhat.com/show_bug.cgi?id=893179#c16 So pretty much in every possible way this is broken. I don't see how anyone says dual boot is supported on CentOS. It's barely supported on Fedora where right now only Windows on BIOS or 'UEFI without Secure Boot' are supported configurations. It's not even supported to install Fedora after CentOS, there's no release criteria saying that it must work, therefore there's no blocking releases on that bug, therefore it's considered not supported. -- Chris Murphy
On 07/02/2015 11:51 AM, Chris Murphy wrote:> On Thu, Jul 2, 2015 at 2:43 AM, ken <gebser at mousecar.com> wrote: >> On 07/01/2015 05:10 PM, Jonathan Billings wrote: >>> >>> >>>> On Jul 1, 2015, at 12:20, Chris Murphy <lists at colorremedies.com> wrote: >>>> >>>> My understanding is CentOS doesn't really support dual-boot anyway, >>>> whereas Fedora does. >>> >>> >>> Nope. CentOS 5, 6 and 7 all support dual-boot. > > Considering CentOS 7, at least, doesn't include ntfsprogs, the > installation of CentOS can't support shrink or discovery of Windows in > order to create a GRUB menu entry for it. That tools exist the user > can make this work after installation is not at all what I'd consider > "supported". > > >> Since Linux first came out in '92, every distro I've used-- SLS, Slackware, >> Redhat, Suse, CentOS, and probably one or two others-- *all* have allowed >> dual-boot. The feature is built into grub, and lilo before that. Anyone >> who put together a distro which didn't support dual-boot would have to take >> the feature out-- rewrite the code (and why do that just to take out a >> perfectly functioning feature?)--, else use some other boot loader... e.g., >> the Raspberry Pi distros don't support dual-boot AFAIK. > > Dual boot support has a large number of dependencies, it's not just > dependent on GRUB doing the right thing. When ntfsprogs isn't included > on installation media, for example, Windows dual boot isn't going to > happen at install time, you have to do it manually after installing > ntfsprogs. > > .... <snip>I guess it depends on one's definition of "support". Your definition seems to be more demanding... which often is a good thing, urging Linux on to be better. Me, I didn't use the word "support" at all. I only said that I've done it on every one of my Linux systems since 1992 (except Raspberry Pi's). Yes, a little manual work was needed on the Windows side, but this was well documented and frankly not that hard. Since I've done it-- numerous times-- I'm not readily persuaded that it's impossible to do. Sure, it would be nice during the install process to simply click a button for "Yes, I want to dual-boot with Windows (or whatever)" and it would just happen. Yeah, I'd like that. On the other hand, what other (i.e., commercial) OSs support/allow/permit dual-booting? Given all the code for Linux is readily available to Apple and MS, it's much, much simper for them. The exact opposite is true for Linux developers. With VMs solid and much more useful and with deep market penetration, the need for dual-booting seems to be fading anyway.
Chris Murphy
2015-Jul-02 17:32 UTC
[CentOS] dual-booting <- Re: installing Cents os server 7.0
On Thu, Jul 2, 2015 at 10:42 AM, ken <gebser at mousecar.com> wrote:> I guess it depends on one's definition of "support". Your definition seems > to be more demanding... which often is a good thing, urging Linux on to be > better. > > Me, I didn't use the word "support" at all. I only said that I've done it > on every one of my Linux systems since 1992 (except Raspberry Pi's). Yes, a > little manual work was needed on the Windows side, but this was well > documented and frankly not that hard. Since I've done it-- numerous times-- > I'm not readily persuaded that it's impossible to do.It's effectively impossible. Very few people know how to do this. Fewer care to learn when there are platforms that make this much easier.> Sure, it would be nice during the install process to simply click a button > for "Yes, I want to dual-boot with Windows (or whatever)" and it would just > happen. Yeah, I'd like that. On the other hand, what other (i.e., > commercial) OSs support/allow/permit dual-booting?Windows explicitly permits dual boot with Windows. So does OS X, but in addition can even set up the system to accept a Windows installation. So I personally think it's embarrassing that RH/CentOS/Fedora can't reliably install N+1 after version N, and for both of them to be bootable; *and* for both of them to do kernel updates that cause their respective boot entries to be automatically updated (and visible to the user) as well. That part is completely busted in GRUB because instead of using configfile to point to distro specific grub.cfg, it creates a whole new boot entry for that first distro instance in a grub.cfg that's only available to the 2nd instance. It's an ugly mess, bad UX all around.>Given all the code for > Linux is readily available to Apple and MS, it's much, much simper for them. > The exact opposite is true for Linux developers.Yeah I don't buy that. The way Windows, OS X, and Linux boot are not secrets. It's well understood by those who know this, but getting developers to fix GRUB is what's hard. I explained to GRUB upstream what needs to be done to get a Mac to boot OS X properly from GRUB, but no one cares to actually do the work. So not only does that not get done, but the old code that wrongly puts in bad OS X menu entry that panics the system, isn't removed. It's 2x the bad UX of two Linux systems coexisting. And has nothing to do with how proprietary those other systems are. And, to underscore it again, Linux code is available to Linux developers, and yet the most common outcome for Linux A + Linux B dual boot is Linux B literally *enjoys* stepping on Linux A. The cooperation that exists with the kernel? It's nearly the opposite level of cooperation when it comes to OS installation and booting. Every distro reinvents the wheel, and has zero concern about how hostile their installer is to an existing Linux installation that isn't their own. Hell, the RH/CentOS/Fedora eco system borks it's own prior installations! So it has nothing to do with code availability. It has to do with not caring (and to some degree the resources to care).> With VMs solid and much more useful and with deep market penetration, the > need for dual-booting seems to be fading anyway.Sure, but increasingly it's Linux being put into that VM. Not the other way around. And that's due to things like dual-GPU systems simply working better, automatically, with no fuss, on Windows and OS X. This is at least variable on Linux, still. And yes a lot of this is because of proprietary behaviors on the part of Nvidia and AMD. So the reasons why this is difficult on free software are all valid, but it's also valid when users just give up and use a different platform because they don't have to deal with these sorts of problems. -- Chris Murphy
On Jul 2, 2015, at 9:51 AM, Chris Murphy <lists at colorremedies.com> wrote:> >> On 07/01/2015 05:10 PM, Jonathan Billings wrote: >>> >>> Nope. CentOS 5, 6 and 7 all support dual-boot. > > Considering CentOS 7, at least, doesn't include ntfsprogs, the > installation of CentOS can't support shrink or discovery of Windows in > order to create a GRUB menu entry for it. That tools exist the user > can make this work after installation is not at all what I'd consider > "supported?.That?s a really narrow interpretation. The behavior you describe, where the OS installer can shrink an existing NTFS partition to allow room for Linux partitions doesn?t go back to 1992, yet we managed to dual-boot back then. Would it be *nice* if RHEL/Fedora/CentOS could do this? Sure. Is it a necessary prerequisite? Absolutely not.
On Thu, Jul 2, 2015 at 4:06 PM, Warren Young <wyml at etr-usa.com> wrote:> On Jul 2, 2015, at 9:51 AM, Chris Murphy <lists at colorremedies.com> wrote: >> >>> On 07/01/2015 05:10 PM, Jonathan Billings wrote: >>>> >>>> Nope. CentOS 5, 6 and 7 all support dual-boot. >> >> Considering CentOS 7, at least, doesn't include ntfsprogs, the >> installation of CentOS can't support shrink or discovery of Windows in >> order to create a GRUB menu entry for it. That tools exist the user >> can make this work after installation is not at all what I'd consider >> "supported?. > > That?s a really narrow interpretation. > > The behavior you describe, where the OS installer can shrink an existing NTFS partition to allow room for Linux partitions doesn?t go back to 1992, yet we managed to dual-boot back then.I've suggested that the distribution doesn't support dual boot if it has no hand in making it possible. The user doing this on their own manually is user enabled and supported. The distro has nothing to do with it.> Would it be *nice* if RHEL/Fedora/CentOS could do this? Sure. Is it a necessary prerequisite? Absolutely not.I disagree. Along the same lines as this, relating primarily to security and privacy: http://mjg59.dreamwidth.org/32686.html I'll argue that the four freedoms aren't meaningful when they only benefit a scant minority. And the end result is, increasingly, developers are picking Macs because so many basic UI/UX things are handled so well and continue to be a PITA on Linux (desktop in particular). http://mjg59.dreamwidth.org/31714.html -- Chris Murphy