[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Steven Woody]

Hi,

The manual is not so clear.  I want to boot from a remote image and
mount remote root filesystem.  It seems i've done the server side
setup respecting to the manual, but for u-boot usage ( target side )
to do this, i am not so clear.  Would anyone please show me simple
steps?  Thanks in advance.

-- 
woody

then sun rose thinly from the sea and the old man could see the other
boats, low on the water and well in toward the shore, spread out
across the current.

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Wolfgang Denk]

In message <ed4892840805120302l3e9a762bg23be7dbdb858c238@mail.gmail.com> you wrote:
> 
> The manual is not so clear.  I want to boot from a remote image and
> mount remote root filesystem.  It seems i've done the server side
> setup respecting to the manual, but for u-boot usage ( target side )
> to do this, i am not so clear.  Would anyone please show me simple
> steps?  Thanks in advance.

Maybe you can point out which parts of the manual are not clear
enough, so that we can improve the documentation?

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"In matrimony, to hesitate is sometimes to be saved."        - Butler

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Steven Woody]

Dear Denk,

Q1:

Both 5.9.5.1 ( http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
) and 5.9.5.6 (
http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
) talk about booting image via network, but there are only few lines
of description about these commands.  I don't know which one I should
use, tftpboot or bootp? And, for each one, what's the requirement on
server side?  I've done works described in 4.6, 4.7, 4.8 to setup the
server, but I don't sure which one ( tftp, dhcp, nfs ) will really be
used.


Q2:

in 9.6.3 ( Root File System on a cramfs File System ), the manual
taught how to make a root filesystem image (cramfs), but in the
installation ISO, i dont find necessary files rootfs.tar.gz and
devices.tar.gz mentioned in the instructions.  Where should I get
them?  On the other hand, after installed the eldk, I've already got a
root filesystem in /installation/path/arm, so i think it will be very
good building a root filesystem image from this directory, but in the
manual, I dont find instructios telling me how.


Thank you very much.


On Tue, May 13, 2008 at 2:29 AM, Wolfgang Denk <wd@denx.de> wrote:
> In message <ed4892840805120302l3e9a762bg23be7dbdb858c238@mail.gmail.com> you wrote:
>>
>> The manual is not so clear.  I want to boot from a remote image and
>> mount remote root filesystem.  It seems i've done the server side
>> setup respecting to the manual, but for u-boot usage ( target side )
>> to do this, i am not so clear.  Would anyone please show me simple
>> steps?  Thanks in advance.
>
> Maybe you can point out which parts of the manual are not clear
> enough, so that we can improve the documentation?
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> "In matrimony, to hesitate is sometimes to be saved."        - Butler
>



-- 
woody

then sun rose thinly from the sea and the old man could see the other
boats, low on the water and well in toward the shore, spread out
across the current.

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Wolfgang Denk]

Dear Steven,

in message <ed4892840805121852t46d4c4d0rd52a9eb129121f7b@mail.gmail.com> you wrote:
> 
> Q1:
> 
> Both 5.9.5.1 ( http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
> ) and 5.9.5.6 (
> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
> ) talk about booting image via network, but there are only few lines
> of description about these commands.  I don't know which one I should
> use, tftpboot or bootp? And, for each one, what's the requirement on

That depends on what you want to do. Do you understand the differecne
between TFTP and BOOTP (resp. DHCP) protocols?

> server side?  I've done works described in 4.6, 4.7, 4.8 to setup the
> server, but I don't sure which one ( tftp, dhcp, nfs ) will really be
> used.

You can use any of these, depending on what you want to do.

If in doubt, just follow the detailed instructions in section
"7.  Booting Embedded Linux".

> Q2:
> 
> in 9.6.3 ( Root File System on a cramfs File System ), the manual
> taught how to make a root filesystem image (cramfs), but in the
> installation ISO, i dont find necessary files rootfs.tar.gz and
> devices.tar.gz mentioned in the instructions.  Where should I get

Please re-read section "9.6. Root File System: Design and  Building";
it contains a detailed step-by-step instruction.


Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Too many people are ready to carry the stool when the piano needs  to
be moved.

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Steven Woody]

On Tue, May 13, 2008 at 2:07 PM, Wolfgang Denk <wd@denx.de> wrote:
> Dear Steven,
>
> in message <ed4892840805121852t46d4c4d0rd52a9eb129121f7b@mail.gmail.com> you wrote:
>>
>> Q1:
>>
>> Both 5.9.5.1 (
http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
>> ) and 5.9.5.6 (
>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
>> ) talk about booting image via network, but there are only few lines
>> of description about these commands.  I don't know which one I should
>> use, tftpboot or bootp? And, for each one, what's the requirement on
>
> That depends on what you want to do. Do you understand the differecne
> between TFTP and BOOTP (resp. DHCP) protocols?

I understand tftp and bootp as a function of current DHCP, but I don't
know how tftp and bootp is related.  Would you suggest me something to
read? Thank you.

>
>> server side?  I've done works described in 4.6, 4.7, 4.8 to setup the
>> server, but I don't sure which one ( tftp, dhcp, nfs ) will really be
>> used.
>
> You can use any of these, depending on what you want to do.
>
> If in doubt, just follow the detailed instructions in section
> "7.  Booting Embedded Linux".

Okay, I will re-read section 7 and 9 and go back here if still have
questions.  So much thank you for your help.


>
>> Q2:
>>
>> in 9.6.3 ( Root File System on a cramfs File System ), the manual
>> taught how to make a root filesystem image (cramfs), but in the
>> installation ISO, i dont find necessary files rootfs.tar.gz and
>> devices.tar.gz mentioned in the instructions.  Where should I get
>
> Please re-read section "9.6. Root File System: Design and  Building";
> it contains a detailed step-by-step instruction.
>
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> Too many people are ready to carry the stool when the piano needs  to
> be moved.
>



-- 
woody

then sun rose thinly from the sea and the old man could see the other
boats, low on the water and well in toward the shore, spread out
across the current.

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Jerry Van Baren]

Steven Woody wrote:
> On Tue, May 13, 2008 at 2:07 PM, Wolfgang Denk <wd@denx.de> wrote:
>> Dear Steven,
>>
>> in message <ed4892840805121852t46d4c4d0rd52a9eb129121f7b@mail.gmail.com> you wrote:
>>> Q1:
>>>
>>> Both 5.9.5.1 (
> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
>>> ) and 5.9.5.6 (
>>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
>>> ) talk about booting image via network, but there are only few lines
>>> of description about these commands.  I don't know which one I should
>>> use, tftpboot or bootp? And, for each one, what's the requirement on
>> That depends on what you want to do. Do you understand the differecne
>> between TFTP and BOOTP (resp. DHCP) protocols?
> 
> I understand tftp and bootp as a function of current DHCP, but I don't
> know how tftp and bootp is related.  Would you suggest me something to
> read? Thank you.

Bootp is a boot protocol that allows a system to query a server to 
figure out what IP it is assigned and what executable file to load 
(typically via TFTP).  DHCP is the successor to bootp.

TFTP is a file transfer protocol that allows a system to load its 
executable (typically) file from the server.

<http://www.linuxjournal.com/article/5465> (ignore RARP, it is deprecated).

HTH,
gvb

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Steven Woody]

On Wed, May 14, 2008 at 10:05 AM, Jerry Van Baren <gvb.uboot@gmail.com> wrote:
> Steven Woody wrote:
>>
>> On Tue, May 13, 2008 at 2:07 PM, Wolfgang Denk <wd@denx.de> wrote:
>>>
>>> Dear Steven,
>>>
>>> in message <ed4892840805121852t46d4c4d0rd52a9eb129121f7b@mail.gmail.com>
>>> you wrote:
>>>>
>>>> Q1:
>>>>
>>>> Both 5.9.5.1 (
>>
>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
>>>>
>>>> ) and 5.9.5.6 (
>>>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
>>>> ) talk about booting image via network, but there are only few lines
>>>> of description about these commands.  I don't know which one I should
>>>> use, tftpboot or bootp? And, for each one, what's the requirement on
>>>
>>> That depends on what you want to do. Do you understand the differecne
>>> between TFTP and BOOTP (resp. DHCP) protocols?
>>
>> I understand tftp and bootp as a function of current DHCP, but I don't
>> know how tftp and bootp is related.  Would you suggest me something to
>> read? Thank you.
>
> Bootp is a boot protocol that allows a system to query a server to figure
> out what IP it is assigned and what executable file to load (typically via
> TFTP).  DHCP is the successor to bootp.
>
> TFTP is a file transfer protocol that allows a system to load its executable
> (typically) file from the server.
>
> <http://www.linuxjournal.com/article/5465> (ignore RARP, it is deprecated).
>
> HTH,
> gvb
>

Thank you Jerry, I now understand TFTP and BOOTP should on a same
host, the 'filename' parameter in dhcpd.conf specified the boot image
file which can be download via tftp by u-boot. And, nfs server can be
on another server, the 'next-server' parameter in dhcpd.conf specified
the ip address of the nfs server.

But one thing I am not clear:  the u-boot's bootargs variable uses
  nfsroot=${serverip}:${rootpath}
are the 'serverip' and 'rootpath' set by querying BOOT server in
u-boot's bootp stage? if so, serverip should equals to the next-server
parameter in dhcpd.conf, and rootpath should equal to root-path
parameter in dhcpd.conf.  You see, in u-boot, it is rootpath, but in
dhcpd.conf, it is root-path,  is there a typo in the u-boot manual?

And, in the u-boot manual, I see, the `filename' parameter in
dhcpd.conf is something like /tftproot/uImage, but I think it should
be /uImage, because the /tftproot should be the root path of tftp
server, to the client, the path name should be /uImage, am I right?

Thank you very much.



 $rootpath, was this variable set by querying BOOTP server?

-- 
woody

then sun rose thinly from the sea and the old man could see the other
boats, low on the water and well in toward the shore, spread out
across the current.

[U-Boot-Users] How to use tftp to book kernel image and mount remote root fs

[Jerry Van Baren]

Steven Woody wrote:
> On Wed, May 14, 2008 at 10:05 AM, Jerry Van Baren <gvb.uboot@gmail.com> wrote:
>> Steven Woody wrote:
>>> On Tue, May 13, 2008 at 2:07 PM, Wolfgang Denk <wd@denx.de> wrote:
>>>> Dear Steven,
>>>>
>>>> in message <ed4892840805121852t46d4c4d0rd52a9eb129121f7b@mail.gmail.com>
>>>> you wrote:
>>>>> Q1:
>>>>>
>>>>> Both 5.9.5.1 (
>>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.1.
>>>>> ) and 5.9.5.6 (
>>>>> http://www.denx.de/wiki/view/DULG/UBootCmdGroupDownload#Section_5.9.5.6.
>>>>> ) talk about booting image via network, but there are only few lines
>>>>> of description about these commands.  I don't know which one I should
>>>>> use, tftpboot or bootp? And, for each one, what's the requirement on
>>>> That depends on what you want to do. Do you understand the differecne
>>>> between TFTP and BOOTP (resp. DHCP) protocols?
>>> I understand tftp and bootp as a function of current DHCP, but I don't
>>> know how tftp and bootp is related.  Would you suggest me something to
>>> read? Thank you.
>> Bootp is a boot protocol that allows a system to query a server to figure
>> out what IP it is assigned and what executable file to load (typically via
>> TFTP).  DHCP is the successor to bootp.
>>
>> TFTP is a file transfer protocol that allows a system to load its executable
>> (typically) file from the server.
>>
>> <http://www.linuxjournal.com/article/5465> (ignore RARP, it is deprecated).
>>
>> HTH,
>> gvb
>>
> 
> Thank you Jerry, I now understand TFTP and BOOTP should on a same
> host, the 'filename' parameter in dhcpd.conf specified the boot image
> file which can be download via tftp by u-boot. And, nfs server can be
> on another server, the 'next-server' parameter in dhcpd.conf specified
> the ip address of the nfs server.

Next-server is where u-boot will go to with tftp to get the executable 
file.  Usually you don't use this, but it depends on how you have your 
network and servers configured.

You can download an executable via NFS, but (if I understand correctly), 
bootp/DHCP doesn't know how to specify to get the linux image over 
NFS... it is a separate "nfs" command which you can run manually or in a 
script.  In other words, saying "bootp/DHCP" and "NFS" in the same 
sentence doesn't make sense.

My usage of nfs has only been via linux, in which case linux is running 
and bootp/dhcp are a fading memory (DHCP provides the IP lease and 
little else when linux is in control).

> But one thing I am not clear:  the u-boot's bootargs variable uses
>   nfsroot=${serverip}:${rootpath}
> are the 'serverip' and 'rootpath' set by querying BOOT server in
> u-boot's bootp stage? if so, serverip should equals to the next-server

serverip env variable can be set by you to specify to u-boot who to get 
the information from, or it can be provided by your DHCP (/bootp?) 
server.  It depends on your DHCP server's capabilities and configuration.

Ref: <http://www.denx.de/wiki/DULG/UBootEnvVariables> (scroll all the 
way to the bottom of the page).

> parameter in dhcpd.conf, and rootpath should equal to root-path
> parameter in dhcpd.conf.  You see, in u-boot, it is rootpath, but in
> dhcpd.conf, it is root-path,  is there a typo in the u-boot manual?

You are challenging the limits of my knowledge.  :-/  I'm sure it isn't 
a typo and I'm too tired right now to improve my knowledge by grepping 
the code.  :-(  I believe the env variable rootpath is set to what the 
DHCP server provides as the root-path option.

> And, in the u-boot manual, I see, the `filename' parameter in
> dhcpd.conf is something like /tftproot/uImage, but I think it should
> be /uImage, because the /tftproot should be the root path of tftp
> server, to the client, the path name should be /uImage, am I right?

Whether you need /tftproot or not depends on how you've configured your 
tftp server.  You can configure your tftp server to change its root 
directory (-s option) or not.  If you use -s /tftproot, you don't want 
the /tftproot.  If you don't use -s, you need to specify the full path.

Hint: Use tftp on a "normal" linux system (preferably not your server) 
to verify you have the right path and permissions and can download the 
file from your server.  You can try different combinations faster that way.

> Thank you very much.
> 
> 
>  $rootpath, was this variable set by querying BOOTP server?

Best regards,
gvb