Bootloader Limitation Problem

[Just17]

Just17
Your edit nice, I was just thinking about this boot business decided to leave this just yet, saved me wrecking my brain more.Yielded to temptation and have just finished another unsuccessful process. Using full pathnames and keeping things nice an tidy. Again the mkisofs fails with the .sqf* problem, recover by using option -r  (I had not got around to add the boot bit).

kjpetire
This look at mylivecd had not escaped me, it was more for my educational exercise I thought keep it nice and simple.  I got more than I bargained for.  

wedgetail ......  the  -R  option is required.

See the commands in the tips & tricks thread I posted .....  link in post above.

[wedgetail]

Just17
I am still active on this, I have read your tips link too but I have however overstretched myself a bit will have to relax a bit again.  I have two new ISO's I made via a directory structure I set up to suit me, they both show workable .sqfs but I am going to make sure they will go through the liveHDD path and make installable working systems.

One of those ISO's was made using your command line statement but modified to my path structure, .sqfs looked fine first run.

I will also check out following more closely your tips page but I will report here not to clutter your work.

kjpetrie   in his last post here made a comment about the kernel, I have to check with my runs but I did forget to make sure that was the case.  The failing runs may be on a slightly older kernel.  

[Just17]

The commands in the tips thread should be good for all 2012 and later OSs, and even older ones ....  I haven't checked.

Worst case would be to change the compression option to  lzma  for old kernels (2.6.37 and older).

By your posts you are using any of those.

[wedgetail]

Just17
I am looking at the options you have specified, the following has, what is between my ears arguing 

-boot-load-size 4  Specifies the number of "virtual" (512-byte) sectors to load in no-emulation mode. The default is to load the entire boot file. Some BIOSes may have problems if this is not a multiple of 4.

From mkisofs help file:

  -boot-load-size #           Set numbers of load sectors

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[gert@localhost isolinux]$ ls -l isolinux.bin
-rw-r--r-- 1 root root 14336 Jan 19 11:08 isolinux.bin
[gert@localhost isolinux]$
1.. the boot file size is 14,336 bytes

2.. default is to load the entire boot file

3.. by specifying no size the whole file is loaded

4.. by specifying a number of 4 --> 2048 bytes (segment size on optical disks ?) only 2048 bytes loaded?

Is there something context sensitive in the sentences that I fail to understand? I am tempted to say perhaps this should be a number of 32 which would cover the boot file size. 

[Just17]

I saw that but left the setting as specified by mylivecd without delving into it.

I didn't have time to get into it .....  if you get further info about that option please post a link, thanks 

[wedgetail]

Just17
If it used in mylivecd at this stage I will accept it has been tested out long enough plus I can also interpret the 4 as the figure that ensures that normal sector reading software can handle a "new unit" which is 4 times as big. Somebody more experienced in lower level programming could in the mean time possibly provide the answer with much less effort. 

If I go further and find something I will link to it.

I now have quite a number of empty partitions and can now move on to creating liveHDDs from what I believe to be two good iso's, instead of assuming I will take them right through to installing new OS on HHDs.  

[Just17]

I look forward to the results of those tests 

[wedgetail]

Just17
This will be a work in progress as I see 3 iso's to be tested, 1st one done by command line statement

I am using the OS that I am starting to suspect:

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[root@localhost zz]# mkisofs -R -b isolinux/isolinux.bin -no-emul-boot -boot-load-size 4 -boot-info-table -o /zmkiso/just17testmethod.iso /zz
This was your initial set of options you chose for mkisofs, the ISO generated without any problem.
LiveHDD generation sailed through with flying colours, I even got the naming I wanted  . The liveHDD placed on /dev/sda8
Running/booting the the liveHDD and then installing to KDE32 to /dev/sdb15 without any problem.
Stanzas moved into to master menu.lst
The installed KDE32 rebooted and immediately fully updated then installed Opera and had a quick trouble free look around on Forum and the net.
 

The simple command line I used for generating my useable ISO had one option -r:

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[root@localhost zz]# mkisofs -o /zmkiso/NewOption_KDE32-2012.12.iso -r  /zz
LiveHDD placed on /dev/sda8  (same partition where your liveHDD is I am just reminding viewers that one can have a string of liveHDD's sitting in a partition, even one already having a full linux file system as well. From management point of view not recommended though   gets a bit messy)
Running the liveHDD and then installing PCLinuxOS KDE32 to /dev/sda20 no problem
Stanza moved to master menu.lst and system rebooted.
Immediately did a full update and then installed Opera.  Had a quick look around and now writing this update from the system.

With 3 hard disks installed that is a first, actually think this is the first time ever.  On your system I even checked that the bootloader.pm was modifed.  This is looking good.  


Just17 full options set used for generating the ISO:

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[root@localhost zz]# mkisofs -l -R -J -b isolinux/isolinux.bin -no-emul-boot -boot-load-size 4 -boot-info-table  -hide-rr-moved -cache-inodes -no-bak -pad -v -v   -o  /zmkiso/Just17-full-options.iso   /zz
No problem, file size the same as the other two.  
The generated report had some interesting extra lines.
liveHDD file naturally placed in /dev/sda8 with the other two  
Stanza placed in master menu.lst system rebooted
Fully upgraded and then Opera installed, a bit of looking around nothing noticed to be out of place.


The Just17-full-options.iso was eventually burned successfully at 4x to Verbatim DVD-RW, after I had forced fully formatted/erased it, using:

Code: [Select]

[root@localhost gert]# dvd+rw-format -force=full /dev/sr0
I had it waiting for an opportune moment to actually have to do something about the apparent lack mounting the disk again after the write, really weird. It was burned using the installed via liveHDD and fully updated system based on the same ISO. The liveCD booted on my system nicely. I am using it now and half accidentally fully updated the liveCD and also installed Opera.

I have also made bootable USB Toshiba 4GB stick, just figuring out which pc will be easiest to get to boot from USB, think it will be the little Toshiba Tecra I5


This morning I have tested the USB stick on my Toshiba Tecra, has a nice facility to easily switch boot device. Worked flawlessly. 

My plan now will be to make a mylivecd of one of the new installs but with some of my basic customisations.

[Just17]

Hi, glad you had success with it ......  the ISO would have been larger than the original, and the loop image quicker to produce, due to lack of XZ compression if you used the original command for that too.

[wedgetail]

A good step forward, see my last post bottom section.

Now the question: I have a fully updated liveCD running can I make a mylivecd of this before I clos the computer and loose it all?   

[Just17]

A good step forward, see my last post bottom section.

Now the question: I have a fully updated liveCD running can I make a mylivecd of this before I clos the computer and loose it all?   

OK, re-read the previous post containing edits.
Excellent results it seems.
Everything seemed to come together properly. 

mylivecd:
              the liveOS is running in memory; there is no default Swap space; mylivecd is heavy on resources.

So, my opinion (at this time) would be that it is possible .....  if the necessary resources can be allocated.
If you happen to be running in persistent mode, you could get several attempts at it .....  but if not I guess you only have the one chance 

Was this question not raised some time ago? ......  I seem to recall it vaguely ...... so my opinion might be completely incorrect ........ memory lapse 

[wedgetail]

I have updated the "testing post" with positive USB boot stick as well.  I think your tips and tricks page is likely to be solid.  If I have the enthusiasm I will tidy of the number of files I created doing this and probably have a bit of a break again. Eventually the modification hopefully will be included in the rolling ISOs.

The exercise gave me an opportunity to check out my super duper text editor running under wine, It stood up really well. I remember learning a lot of scripting some years ago trying to get it to work more integrated with pclinuxos.  The later version of wine has obsoleted any special customisations. It is a bit like Kate and I did try to get Kate to work in similar manner but I did not make it.

During this I really should have tried the "Project" option, you give a name to the project and this allows you top open a group of files in one hit. Initially I thought no need for that I will only use one file for records, oh boy, went well beyond 10, I really should have listened to my inner voice which told me I would be wrong.      Hmmm I think this is a digression.

[Just17]

I have updated the "testing post" with positive USB boot stick as well.  I think your tips and tricks page is likely to be solid.  If I have the enthusiasm I will tidy of the number of files I created doing this and probably have a bit of a break again. Eventually the modification hopefully will be included in the rolling ISOs.
....

Yes for the bootloader.pm edit, it won't be needed in the future.
Nevertheless there are other reasons for wanting to break apart an ISO ......  such as adding some files to the guest desktop for a particular friend or family member/s.

A nice way to send holiday video or such .....  embedded in the OS ......  they get to use Linux without even realising it 

As far as I can presently determine the tips & tricks post is OK now .....  unless you have something to highlight that needs changing?

It's been fun