PCL Magazine Article "dd" (SOLVED)

[Yankee]

The recent magazine had a comprehensive article for "dd"

This command here:

dd if=/path/livecd.iso of=/dev/sdb bs=4k conv=notrunc;sync

Well it is supposed to boot the livecd iso from a flash drive (sdb).
Sometimes it does and sometimes it doesn't.

I have read where the iso has to be a "hybrid" iso and/or the target
flash drive has to be a virgin drive formatted with FAT32 for this
to succeed.  

Any further accurate technical info available concerning this command.
A little confused it wasn't included in the PCL Magazine article.  When it
works it sure is convenient.

Thanks in advance for your response.

FF

[Just17]

I can't see how having any format can affect it .........  as everything gets overwritten.

You should convert the ISO to Hybrid, IIRC, before doing this.

You have a choice .........   you can convert the ISO to write to a partition on the USB stick (it must be a primary partition I think) and you can put a separate boot manager on another (any) partition to boot the ISO.

The type of Hybrid you create determines which scheme you use to install it .........  full USB drive or a partition of the drive.

I use this to prepare the ISO for installation on a partition .........

isohybrid -partok "$ISO_FILE"

Be aware that the original ISO is converted, so you might wish to work on a copy.

It is common practice here to have a 'live' install on one partition, done with LiveUSB Converter, and use another partition for Hybrid installs, with a general boot stanza to launch whatever ISO is written to the partition.

Good luck  

EDIT:
            This wee script might be of interest to install to a partition, provided you already have the stick booting from another partition as described above ...
http://dl.dropbox.com/u/5838889/iso2usb-Alpha-0.4.sh

[Yankee]

The type of Hybrid you create determines which scheme you use to install it .........  full USB drive or a partition of the drive.

I use this to prepare the ISO for installation on a partition .........

isohybrid -partok "$ISO_FILE"

Be aware that the original ISO is converted, so you might wish to work on a copy.

Hi,

Is it safe to say the hybrid iso would boot from a full USB drive without
the -partok option ?   Haven't tried it yet but that would be my first choice.

THX

[Just17]

The type of Hybrid you create determines which scheme you use to install it .........  full USB drive or a partition of the drive.

I use this to prepare the ISO for installation on a partition .........

isohybrid -partok "$ISO_FILE"

Be aware that the original ISO is converted, so you might wish to work on a copy.

Hi,

Is it safe to say the hybrid iso would boot from a full USB drive without
the -partok option ?   Haven't tried it yet but that would be my first choice.

THX

Yes, but it will consume the full size of the USB device, regardless the requirements of the ISO itself.

So it depends on the relative sizes of ISO and drive as to how much wastage there might be.

I most certainly won't be putting a 700MB ISO on my 16GB USB stick in this manner.

Putting it on a 1GB partition I have access to the other 15GB of space.

[Yankee]

Yes, but it will consume the full size of the USB device, regardless the requirements of the ISO itself.

So it depends on the relative sizes of ISO and drive as to how much wastage there might be.

I most certainly won't be putting a 700MB ISO on my 16GB USB stick in this manner.

Putting it on a 1GB partition I have access to the other 15GB of space.

Hi,

Well I finally had some time to get back to this.   Ran isohybrid livecd.iso
and then ran dd if=livecd.iso of=/dev/sdb.      Very quick also.    Booted.

Ran a non-PCL iso and it did not take up the whole drive, the remainder
was clearly visible to format, mount and use.    The PCL iso did take up the
whole drive.  Everything was the iso and located at /dev/root.   

I think a hybrid iso can still be burned to a CD but don't have one to test on.

So it's a quick way to look at an iso.

THX.

FF