how to build iso file from usb stick

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rahulvishwa81
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Joined: 2014/03/07 05:19:05

how to build iso file from usb stick

Post by rahulvishwa81 » 2021/10/07 15:23:16

hi to all, I've centos 7. And i want to build from usb stick to iso_on_disk_drive.iso. how to do that. I tried following command :
dd if=/dev/cdrom of=/home/username/iso-name.iso
but it copies all 16 GB from pen drive. i want only 9.5 GB out of 32 GB. how to do that.

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TrevorH
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Joined: 2009/09/24 10:40:56
Location: Brighton, UK

Re: how to build iso file from usb stick

Post by TrevorH » 2021/10/07 15:58:01

You need to know how many records there are to copy and then use the dd parameter count= and probably also bs= to specify the blocksize of the blocks to copy. Might just be easier to download the iso image from one of the mirrors instead.

BTW, 9.5GB means you have the "Everything" DVD and almost no-one needs that. Everything that can be installed by the installer is contained on the ordinary 4.5GB "dvd1" iso.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

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