Syslinux or GRUB2 - Arch Linux

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Syslinux or GRUB2 - Arch Linux

Postby rustleg » Mon Sep 07, 2015 9:28 am

I intend to try Arch Linux in a MBR system (already running Windows and Linux Mint). It's wiki states:
Warning: GRUB strongly discourages installation to a partition boot sector or a partitionless disk as GRUB Legacy or Syslinux does. This setup is prone to breakage, especially during updates, and is not supported by the Arch developers.
https://wiki.archlinux.org/index.php/GR ... nless_disk

I've come across this before in installing other Linuxes (Ubuntu,Mint) and ignored it. Sometimes (but not recently) GRUB gets updated and screws up BIBM in the MBR, and then I follow the Terabyte guide to recovery. However Arch Linux also supports Syslinux as a bootloader and I haven't seen this warning in relation to Syslinux. So I wondered if it would be more stable to use Syslinux (although at present I have no experience of using it). I'm also looking at whether a separate small boot partition would be useful.

Looking at the Syslinux installation guide it also assumes it will be installed into the MBR, so I expect I'll have to reinstall BIBM afterwards and find a way to get it to switch Syslinux to a partition.

So my questions are:

* Is Syslinux a viable option? (or should I stick with GRUB2 and take the risk of corruption of BIBM)

* Should I install the boot files (whether Syslinux or GRUB2) in a separate boot partition rather than the root partition?

* Pointers to how to recover from Syslinux overwriting BIBM in the MBR?
Russell
rustleg
 
Posts: 97
Joined: Thu Sep 01, 2011 10:01 am

Re: Syslinux or GRUB2 - Arch Linux

Postby TeraByte Support(TP) » Tue Sep 08, 2015 6:11 am

See comments below:

rustleg wrote:
> I intend to try Arch Linux in a MBR system (already running Windows and
> Linux Mint). It's wiki states:
> Warning: GRUB strongly discourages installation to a partition boot sector
> or a partitionless disk as GRUB Legacy or Syslinux does. This setup is
> prone to breakage, especially during updates, and is not supported by the
> Arch developers.
>
> https://wiki.archlinux.org/index.php/GR ... nless_disk
>
> I've come across this before in installing other Linuxes (Ubuntu,Mint) and
> ignored it. Sometimes (but not recently) GRUB gets updated and screws up
> BIBM in the MBR, and then I follow the Terabyte guide to recovery. However
> Arch Linux also supports Syslinux as a bootloader and I haven't seen this
> warning in relation to Syslinux. So I wondered if it would be more stable
> to use Syslinux (although at present I have no experience of using it). I'm
> also looking at whether a separate small boot partition would be useful.
>
> Looking at the Syslinux installation guide it also assumes it will be
> installed into the MBR, so I expect I'll have to reinstall BIBM afterwards
> and find a way to get it to switch Syslinux to a partition.
>
> So my questions are:
>
> * Is Syslinux a viable option? (or should I stick with GRUB2 and take the
> risk of corruption of BIBM)

I have never used syslinux that way either, so can't provide a direct answer. One thing to be sure of is that it's config file (usually syslinux.cfg) will get updated automatically when the kernel package(s) get updated during normal system updates. Essentially all distros do this automatically for Grub. Hopefully that's what Arch means by "supports Syslinux as a bootloader", but I'm not sure of that.

Also, the problem you're describing sounds more like what happens when Grub is installed in the MBR by mistake, and not caused by it being installed in a boot sector. Installing/updating GRUB in the MBR will completely overwrite BIBM, and you won't see BIBM at all on boot. If Grub is installed in a partition boot sector, any kernel update from the distro would not affect BIBM itself at all. The failure mode there would be that Grub/Linux would not boot from the BIBM menu after BIBM otherwise starts normally.

>
> * Should I install the boot files (whether Syslinux or GRUB2) in a separate
> boot partition rather than the root partition?

It may be somewhat safer that way in the case of Grub, but FWIW, I don't do it that way on my own systems. I just have /boot as part of the root partition for simplicity. Here's another thread that gets into this general topic for more reading on it (see the last 3 or 4 posts in the thread):
viewtopic.php?f=3&t=1664&hilit=core.img

>
> * Pointers to how to recover from Syslinux overwriting BIBM in the MBR?

If Arch does support using Syslinux installed to a partition as the system bootloader, then that shouldn't happen. Any updates should not touch the MBR/EMBR, so that BIBM is not affected.
Tom Pfeifer
TeraByte Support
TeraByte Support(TP)
 
Posts: 305
Joined: Wed Aug 31, 2011 9:22 am

Re: Syslinux or GRUB2 - Arch Linux

Postby rustleg » Tue Sep 08, 2015 9:35 am

Thanks Tom. The interesting part of the thread you linked was this: "Despite the warnings, most users don't have any problems from what I've seen. I use grub2 this way myself, including on my main Linux install of Debian, and have never seen any problems through many many updates."

I think all considered I'll stick to using grub2. I seem to remember in the distant past that something corrupted it, but it may just be that I was repartitioning the drive and moved the partition, although recently grub2 seems to survive even that. In any case in the past I've successfully recovered grub2 so this seems the line of least resistance for me. In fact I've even copied a partition to have another instance of the same system on the same drive which meant changing its UUID and editing the UUID in various files (can't remember which ones). Makes me wonder if these warnings are out of date.

So thanks for the advice.

Incidentally I have never used a separate boot partition before, but I'm now thinking of trying it and at least I can take an image which might give me another recovery option for the future.
Russell
rustleg
 
Posts: 97
Joined: Thu Sep 01, 2011 10:01 am


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