why rootfs directory in temp is empty

why rootfs directory in temp is empty

[Guo Hongruan]

Hi guys,
   Today, I build an base-image using OE. And I want to check the content  
of rootfs, but I found the directory rootfs in building directory is  
empty. I remember there was the ontent of the target root filesystem. Why  
have to remove them? Does it means the rootfs directory is unuseful?

Thanks a lot!

-- 
Guo Hongruan, Embedded Linux Consultant
Mobile: +86-0-13484056007
Skype: camelguo
Twitter: camelguo
http://www.gulessoft.com

Re: why rootfs directory in temp is empty

[Mike Westerhof]

Guo Hongruan wrote:
> Hi guys,
>   Today, I build an base-image using OE. And I want to check the content
> of rootfs, but I found the directory rootfs in building directory is
> empty. I remember there was the ontent of the target root filesystem.
> Why have to remove them? Does it means the rootfs directory is unuseful?
> 
> Thanks a lot!
> 

Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
I'm not sure why the change was made to clean it out every build, though.

-Mike (mwester)

Re: why rootfs directory in temp is empty

[Denys Dmytriyenko]

On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
> Guo Hongruan wrote:
> > Hi guys,
> >   Today, I build an base-image using OE. And I want to check the content
> > of rootfs, but I found the directory rootfs in building directory is
> > empty. I remember there was the ontent of the target root filesystem.
> > Why have to remove them? Does it means the rootfs directory is unuseful?
> > 
> > Thanks a lot!
> > 
> 
> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
> I'm not sure why the change was made to clean it out every build, though.

To prevent people from using it as an NFS share and having problems.

-- 
Denys

Re: why rootfs directory in temp is empty

[Frans Meulenbroeks]

2009/12/22 Denys Dmytriyenko <denis@denix.org>:
> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>> Guo Hongruan wrote:
>> > Hi guys,
>> >   Today, I build an base-image using OE. And I want to check the content
>> > of rootfs, but I found the directory rootfs in building directory is
>> > empty. I remember there was the ontent of the target root filesystem.
>> > Why have to remove them? Does it means the rootfs directory is unuseful?
>> >
>> > Thanks a lot!
>> >
>>
>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>> I'm not sure why the change was made to clean it out every build, though.
>
> To prevent people from using it as an NFS share and having problems.

Ehm, can you please clarify why this would cause a problem?
(btw if I recall correctly the rootfs is still there in the work dir,
and anyway you can build a rootfs in a tar.gz file and untar that).

Frans

Re: why rootfs directory in temp is empty

[John Faith]

Frans Meulenbroeks wrote:
> 2009/12/22 Denys Dmytriyenko <denis@denix.org>:
>   
>> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>>     
>>> Guo Hongruan wrote:
>>>       
>>>> Hi guys,
>>>>   Today, I build an base-image using OE. And I want to check the content
>>>> of rootfs, but I found the directory rootfs in building directory is
>>>> empty. I remember there was the ontent of the target root filesystem.
>>>> Why have to remove them? Does it means the rootfs directory is unuseful?
>>>>
>>>> Thanks a lot!
>>>>
>>>>         
>>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>>> I'm not sure why the change was made to clean it out every build, though.
>>>       
>> To prevent people from using it as an NFS share and having problems.
>>     
>
> Ehm, can you please clarify why this would cause a problem?
> (btw if I recall correctly the rootfs is still there in the work dir,
> and anyway you can build a rootfs in a tar.gz file and untar that).
>
> Frans
>   

The first time I tried to boot a system using files from the temp 
rootfs, I quickly found that some parts were missing, like all the /dev 
nodes, due to permissions when constructing the rootfs if I recall 
correctly.

That was a while ago so maybe things are different now, but I'm glad 
that the "wrong" files are removed now to reduce (my) confusion.

,
John

Re: why rootfs directory in temp is empty

[Philip Balister]

On 12/22/2009 05:25 PM, Frans Meulenbroeks wrote:
> 2009/12/22 Denys Dmytriyenko<denis@denix.org>:
>> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>>> Guo Hongruan wrote:
>>>> Hi guys,
>>>>    Today, I build an base-image using OE. And I want to check the content
>>>> of rootfs, but I found the directory rootfs in building directory is
>>>> empty. I remember there was the ontent of the target root filesystem.
>>>> Why have to remove them? Does it means the rootfs directory is unuseful?
>>>>
>>>> Thanks a lot!
>>>>
>>>
>>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>>> I'm not sure why the change was made to clean it out every build, though.
>>
>> To prevent people from using it as an NFS share and having problems.
>
> Ehm, can you please clarify why this would cause a problem?
> (btw if I recall correctly the rootfs is still there in the work dir,
> and anyway you can build a rootfs in a tar.gz file and untar that).

Someone correct me if I get this wrong ...

Since OE does not run as root, the file ownership are not suitable for 
use as a true rootfs. During the assembly of the tarball, the file owner 
information is "fixed" so that if you unpack the tarball as root, the 
files have the proper owners.

So the temporary root file system will not do what people expect.

Philip

Re: why rootfs directory in temp is empty

[Khem Raj]

On Tue, Dec 22, 2009 at 2:46 PM, Philip Balister <philip@balister.org> wrote:
> On 12/22/2009 05:25 PM, Frans Meulenbroeks wrote:
>>
>> 2009/12/22 Denys Dmytriyenko<denis@denix.org>:
>>>
>>> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>>>>
>>>> Guo Hongruan wrote:
>>>>>
>>>>> Hi guys,
>>>>>   Today, I build an base-image using OE. And I want to check the
>>>>> content
>>>>> of rootfs, but I found the directory rootfs in building directory is
>>>>> empty. I remember there was the ontent of the target root filesystem.
>>>>> Why have to remove them? Does it means the rootfs directory is
>>>>> unuseful?
>>>>>
>>>>> Thanks a lot!
>>>>>
>>>>
>>>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>>>> I'm not sure why the change was made to clean it out every build,
>>>> though.
>>>
>>> To prevent people from using it as an NFS share and having problems.
>>
>> Ehm, can you please clarify why this would cause a problem?
>> (btw if I recall correctly the rootfs is still there in the work dir,
>> and anyway you can build a rootfs in a tar.gz file and untar that).
>
> Someone correct me if I get this wrong ...
>
> Since OE does not run as root, the file ownership are not suitable for use
> as a true rootfs. During the assembly of the tarball, the file owner
> information is "fixed" so that if you unpack the tarball as root, the files
> have the proper owners.
>
> So the temporary root file system will not do what people expect.

This is the real cause. Always use the tar file to populate the
root file system even if it is to be nfs mounted

-Khem

Re: why rootfs directory in temp is empty

[Guo Hongruan]

Yea, I understand. Thanks a lot.

I used to check the rootfs directory quickly, to verify whether or not  
some packages have been installed correctly and to check the rootfs size.  
So when I can not find it as usual, I am amazing.

Thank all of you.

在 Wed, 23 Dec 2009 09:07:42 +0800，Khem Raj <raj.khem@gmail.com> 写道:

> On Tue, Dec 22, 2009 at 2:46 PM, Philip Balister <philip@balister.org>  
> wrote:
>> On 12/22/2009 05:25 PM, Frans Meulenbroeks wrote:
>>>
>>> 2009/12/22 Denys Dmytriyenko<denis@denix.org>:
>>>>
>>>> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>>>>>
>>>>> Guo Hongruan wrote:
>>>>>>
>>>>>> Hi guys,
>>>>>>   Today, I build an base-image using OE. And I want to check the
>>>>>> content
>>>>>> of rootfs, but I found the directory rootfs in building directory is
>>>>>> empty. I remember there was the ontent of the target root  
>>>>>> filesystem.
>>>>>> Why have to remove them? Does it means the rootfs directory is
>>>>>> unuseful?
>>>>>>
>>>>>> Thanks a lot!
>>>>>>
>>>>>
>>>>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>>>>> I'm not sure why the change was made to clean it out every build,
>>>>> though.
>>>>
>>>> To prevent people from using it as an NFS share and having problems.
>>>
>>> Ehm, can you please clarify why this would cause a problem?
>>> (btw if I recall correctly the rootfs is still there in the work dir,
>>> and anyway you can build a rootfs in a tar.gz file and untar that).
>>
>> Someone correct me if I get this wrong ...
>>
>> Since OE does not run as root, the file ownership are not suitable for  
>> use
>> as a true rootfs. During the assembly of the tarball, the file owner
>> information is "fixed" so that if you unpack the tarball as root, the  
>> files
>> have the proper owners.
>>
>> So the temporary root file system will not do what people expect.
>
> This is the real cause. Always use the tar file to populate the
> root file system even if it is to be nfs mounted
>
> -Khem
>
> _______________________________________________
> Openembedded-devel mailing list
> Openembedded-devel@lists.openembedded.org
> http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel


-- 
Guo Hongruan, Embedded Linux Consultant
Mobile: +86-0-13484056007
Skype: camelguo
Twitter: camelguo
http://www.gulessoft.com

Re: why rootfs directory in temp is empty

[Koen Kooi]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 22-12-09 23:25, Frans Meulenbroeks wrote:
> 2009/12/22 Denys Dmytriyenko <denis@denix.org>:
>> On Tue, Dec 22, 2009 at 09:05:31AM -0600, Mike Westerhof wrote:
>>> Guo Hongruan wrote:
>>>> Hi guys,
>>>>   Today, I build an base-image using OE. And I want to check the content
>>>> of rootfs, but I found the directory rootfs in building directory is
>>>> empty. I remember there was the ontent of the target root filesystem.
>>>> Why have to remove them? Does it means the rootfs directory is unuseful?
>>>>
>>>> Thanks a lot!
>>>>
>>>
>>> Add IMAGE_KEEPROOTFS = "1" to your local.conf file.
>>> I'm not sure why the change was made to clean it out every build, though.
>>
>> To prevent people from using it as an NFS share and having problems.
> 
> Ehm, can you please clarify why this would cause a problem?

The nfs server doesn't run inside the do_rootfs fakeroot sessions and
hence all the permission will be screwed up. If you can teach OE to
respawn the nfs server inside the fakeroot session, you might get away
with it :)

regards,

Koen
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (Darwin)

iD8DBQFLMdt+MkyGM64RGpERAjY1AJwPkbebEMCnt2oSjDTXxJLDMJibgQCeKiIR
y343rN9hGQCkMzn8Kx6csBQ=
=zSNI
-----END PGP SIGNATURE-----