43p-140 install issues

Leigh Brown leigh at solinno.co.uk
Thu Jan 6 03:30:05 EST 2005

Sven Luther said:
> On Wed, Jan 05, 2005 at 09:45:13AM -0600, Hollis Blanchard wrote:
>> On Jan 5, 2005, at 5:47 AM, Sven Luther wrote:
>> >On Wed, Jan 05, 2005 at 10:49:19AM +0100, Philippe Guyot wrote:
>> >>>BTW, i have another question. I am trying to fix debian-installer
>> >>>to create the prep partition, but i would like to have some info
>> >>>on the expected constraints of said partition. Some tell it has
>> >>>to be entirely in the first 8MB, others the first 5MB, and my
>> >>>powerstack has a 17MB boot partition right now.
>> >>
>> >>All I can say, it's that my boot PReP partition is the 1st and about
>> >>4 MB in size (cannot size it less than 1% of the disk.....)
>> >>second partition is /
>> >>third is swap.
>> >
>> >BTW, for debian, it makes more sense to have the second partition
>> >as swap, and the third as /, i think, since it was decided some
>> >time back to default to root=/dev/sda3, and not sda2.
>> >
>> >>That works for me.
>> >
>> >Until the kernel grows beyond 4MB.
>> The size of that partition depends on firmware limitations. I have
>> definitely seen reports of systems not booting when the PReP boot
>> partition was too large. I think on some systems that has even happened
>> at 8MB.
> Is the problem really the size of the partition, or the space used by
> the kernel. I mean we could make a 100MB partition at start, and since
> we just dd the kernel to it, the kernel would be found at the start of
> the partition, and the firmware probably doesn't care about the real
> size of the partition, as long as it can access all the kernel data we
> added to it, no ?
> Do we have some documentation of the firmware limitations ?
>> In other words, should you need more space than 4-5MB at some point in
>> the future, you cannot simply make a bigger boot partition.
> 8MB would be good, 4-5MB only would probably be a bit just.

Surely if you make the default mkinitrd behaviour a bit more sensible
there won't be a problem.  A compressed 2.6 kernel is about 1.5MB, and
an initrd using MODULES=dep is about 1.5MB, which makes about 3MB,
giving a comfortable amount of space for future growth...



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