[gentoo-user] Is it safe to change the start of the first partition?

[gentoo-user] Is it safe to change the start of the first partition?

[Helmut Jarausch]

Hi,

modern fdisk puts the first partition at block 63  while older version  
have put it at block 1.

Now, I'm going to upgrade an older system.
Is it safe to repartition it by letting the first partition start 63  
and shortening the first partition by 62 blocks?

(I will loose the first partition which doesn't matter in my case.)

Many thanks for sharing your experience,
Helmut.

Re: [gentoo-user] Is it safe to change the start of the first partition?

[Hinnerk van Bruinehsen]

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Hash: SHA1

On 03.07.2012 09:09, Helmut Jarausch wrote:
> Hi,
> 
> modern fdisk puts the first partition at block 63  while older
> version have put it at block 1.
> 
> Now, I'm going to upgrade an older system. Is it safe to
> repartition it by letting the first partition start 63 and 
> shortening the first partition by 62 blocks?
> 
> (I will loose the first partition which doesn't matter in my
> case.)
> 
> Many thanks for sharing your experience, Helmut.
> 

Do you want to resize the partition or do you want to delete and
recreate it?

The second option is no problem, the first could lead to some data
loss (if you are unlucky).
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Re: [gentoo-user] Is it safe to change the start of the first partition?

[Helmut Jarausch]

On 07/03/2012 09:25:20 AM, Hinnerk van Bruinehsen wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> On 03.07.2012 09:09, Helmut Jarausch wrote:
> > Hi,
> >
> > modern fdisk puts the first partition at block 63  while older
> > version have put it at block 1.
> >
> > Now, I'm going to upgrade an older system. Is it safe to
> > repartition it by letting the first partition start 63 and
> > shortening the first partition by 62 blocks?
> >
> > (I will loose the first partition which doesn't matter in my
> > case.)
> >
> > Many thanks for sharing your experience, Helmut.
> >
> 
> Do you want to resize the partition or do you want to delete and
> recreate it?
> 
> The second option is no problem, the first could lead to some data
> loss (if you are unlucky).

I'd like to delete and recreate ONLY the first partition (which is  
small).
The question is, can I keep the other partitions.

As far as I remember, I once deleted the extended partition and tried  
to recreate
logical partitions "at the same place". But that didn't work.

Helmut.

Re: [gentoo-user] Is it safe to change the start of the first partition?

[Hinnerk van Bruinehsen]

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Hash: SHA1

On 03.07.2012 09:42, Helmut Jarausch wrote:
> On 07/03/2012 09:25:20 AM, Hinnerk van Bruinehsen wrote:
>> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
>> 
>> On 03.07.2012 09:09, Helmut Jarausch wrote:
>>> Hi,
>>> 
>>> modern fdisk puts the first partition at block 63  while older 
>>> version have put it at block 1.
>>> 
>>> Now, I'm going to upgrade an older system. Is it safe to 
>>> repartition it by letting the first partition start 63 and 
>>> shortening the first partition by 62 blocks?
>>> 
>>> (I will loose the first partition which doesn't matter in my 
>>> case.)
>>> 
>>> Many thanks for sharing your experience, Helmut.
>>> 
>> 
>> Do you want to resize the partition or do you want to delete and 
>> recreate it?
>> 
>> The second option is no problem, the first could lead to some
>> data loss (if you are unlucky).
> 
> I'd like to delete and recreate ONLY the first partition (which is
> small). The question is, can I keep the other partitions.
> 
> As far as I remember, I once deleted the extended partition and
> tried to recreate logical partitions "at the same place". But that
> didn't work.
> 
> Helmut.
> 
> 

If the first partition is a primary partition it's no issue. If it is
inside a extended partion it gets tricky, because the extended
partition acts like a kind of container.

- From your description I guess it's a boot partition, which normally is
a primary one. In that case just delete it and recreate it afterwards.

Note: you may need to reinstall you bootloader afterwards (due to the
changed partition data) and don't forget to toggle the bootable flag
for that partition.

If it's an extended partition I fear that my experience doesn't
suffice to give you qualifield hints as I try to avoid them.


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Re: [gentoo-user] Is it safe to change the start of the first partition?

[Alex Schuster]

Helmut Jarausch writes:

> modern fdisk puts the first partition at block 63  while older version  
> have put it at block 1.

No, it's older versions that use 63, while the new fdisk uses 2048. This
way the new 4K sectors of huge drives are aligned well. It does not
need to be 2048, as long as it's dividable by 8. But fdisk apparently does
not allow smaller values.

> Now, I'm going to upgrade an older system.
> Is it safe to repartition it by letting the first partition start 63  
> and shortening the first partition by 62 blocks?
> 
> (I will loose the first partition which doesn't matter in my case.)

I thought this would work, but I'm not sure now. But why do you want to
change the partition start anyway?

	Wonko