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{{admon/caution|La traduzione di questa pagina è incompleta. <br/> ''This page is not translated completely. Language target: italian''}}
[[Image:mediawriter-icon.png‎|right]]


<noinclude>
{{admon/warning | ATTENZIONE! | La traduzione di questa pagina wiki NON è disponibile.}}
[[Category:LiveMedia]]
</noinclude>
Questa pagina spiega '''come creare ed usare una Fedora su support0 USB'''. Una live USB memorizzata in una memoria flash, a volte chiamata ''stick'', permette l'avvìo di qualsiasi computer USB-bootable in un ambiente Fedora senza la scrittura fisica del disco rigido. Il Live USB può disporre di un'area per la memorizzazione delle modifiche di sistema, chiamata ''persistent overlay'' (letteralmente, ''strato persistente''). Può anche avere un'area di memorizzazione separata per i dati dell'utente come download e documenti con opzioni per la criptazione. Infine con un'installazione non distruttiva, i file preesistenti e lo spazio in eccesso saranno accessibili dal sistema. Essenzialmente sarebbe un PC tascabile avviabile ovunque possibile.
 
Con gli attuali rilasci di Fedora è possibile masterizzare le immagini d'installazione non-live di Fedora (DVD ed installazioni in rete) in un dispositivo USB, molti utenti le ritengono più convenienti e veloci rispetto ai CD.
 
{{admon/note | Avvìo veloce | Il processo per molti utenti è semplice. Quasi tutte le chiavette USB sono pronte all'uso. Se contengono documenti, non è una cattiva idea farne una copia prima di iniziare.
 
* Scaricare il programma '''LiveUSB Creator''' da http://fedorahosted.org/liveusb-creator se si sta usando Windows oppure installarlo in Linux con il proprio gestore di pacchetti.
* Scaricare l'immagine ISO live da http://fedoraproject.org/get-fedora.
* Inserire la chiavetta ed avviare '''LiveUSB Creator'''.
 
Successivamente riavviare il sistema ed impostare l'avvìo del PC da dispositivo USB -- solitamente è un tasto speciale da premere all'accensione come '''F12'''.
 
Per i dettagli tecnici o per maggiori informazioni sugli strumenti alternativi e di uso avanzato, continuare nella lettura.}}
 
{{admon/warning | Usare UNetbootin | Dopo ogni release, il volontari per il supporto Fedora ricevono delle segnalazioni di problemi con l'installazione delle immagini con Unetbootin. Usare la più recente versione disponibile assicura migliori risultati. Tuttavia usare liveusb-creator può fornire migliori lavori. Se si riscontrano problemi con Unetbootin, si prega di contattare i suoi sviluppatori; non quelli di Fedora .}}
 
 
__TOC__
 
{{admon/important | Creazione dell'immagine ISO Live CD | Un sistema Live USB è creato dalla stessa immagine ISO usata per creare i Live CD/DVD. E' possibile scaricare le immagini Fedora ufficiali dal [http://fedoraproject.org/get-fedora sito]. Consultare [[How to create and use a Live CD]] per maggiori informazioni sulla creazione della propria immagine ISO.}}
 
== Requisiti di sistema ==
 
* Un computer da lavoro con Fedora o Windows. Se si usano altre distribuzioni Linux, considerare l'uso di <code>dd</code> oppure di [http://unetbootin.sourceforge.net/ UNetbootin]. Quest'ultimo è anche disponibile per Mac OS X e Windows, così come nei repository Fedora.
* Un [[wikipedia:USB flash drive|USB flash drive]], conosciuto anche come USB stick, thumb drive, penna USB o jump drive, con 1 GB o più di memoria su filesystem ''vfat'' (standard per quasi tutti i dispositivi USB ''off-the-shelf'' -- di serie)
 
=== Possibilità d'avvìo da dispositivo USB ===
 
Anche se quelli più moderni ne sono capaci, non tutti i computer possono avviarsi da dispositivi a causa di differenti impostazioni del BIOS o capacità di sistema.  Se il PC non ha questa capacità, questa procedura è inutile. Se non se ne è sicuri e si è disposti a scaricare ed installare un immagine nella pennetta USB (possibilmente ripulendola dai dati), il solo rischio sarebbe quello di perder tempo.
 
Se la chiavetta USB non è in buone condizioni, questa procedura potrebbe non riuscire. Osservare i messaggi di errore durante il processo.
 
Alcuni flash drive potrebbero non essere avviabili, anche se l'hardware è in grado di farlo. Potrebbe essere necessario marcarne la partizione come ''avviabile'' o riformattarla. Vedere [[How_to_create_and_use_Live_USB/it#Problems_and_solutions|Problemi e soluzioni]] di seguito per maggiori informazioni.
 
=== Chiavette USB sufficientemente capienti ===
 
Le dimensioni in molte chiavette USB sono indicate sulla confezione o sul corpo esterno stesso.
 
Se non si conoscono o si vogliono controllare, si dovrebbe essere in grado di montarle automaticamente semplicemente inserendole nella porta USB. E' possibile controllarne il contenuto e la capacità usando il file manager grafico. In Linux, si può anche usare il comando {{command|df -h}}:
<pre>
$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
143G  14G  122G  10% /
/dev/sda1              99M  12M  82M  13% /boot
tmpfs                1009M    0 1009M  0% /dev/shm
/dev/sdb1            3.9G  4.0K  3.9G  1% /media/usbdisk
</pre>
 
I drive USB sono usualmente montati in {{filename|/media}} o {{filename|/run/media/username/}}. In questo caso il dispositivo è <code>/dev/sdb1</code>, ha una capacità di 3.9GB ed è quasi vuoto. Come regola si dovrebbero usare chiavette con almeno 1 GB di spazio libero per scriverci un'immagine live ed una di almeno 4 GB per scrivere un'immagine DVD.
 
Notare {{filename|/dev/sdb1}} o equivalente; bisogna specificare il dispositivo se si usa il metodo a linea di comando. E' la stringa che sostituisce USBPARTITIONNAME laddove serve nelle istruzioni di seguito.
 
== Opzionale: ripartizione e formattazione della chiavetta USB ==
 
Se la chiavetta USB ha una partizione FAT con una discreta quantità di spazio libero, la ripartizione/formattazione può essere saltata continuando a seguire i passaggi seguenti. Questo permetterebbe l'aggiunta dell'immagine live Fedora senza la distruzione di dati già presenti. Tuttavia '''è altamente raccomandato fare una copia di tutti i dati prima di procedere''' nel caso qualcosa dovesse andare male.
 
Se si ha qualche difficoltà con l'installazione non-distruttiva, provare prima a resettare il ''master boot record'' (MBR) con l'opzione {{command|--reset-mbr}}.
 
Occasionalmente un filesystem può essere danneggiato rendendo necessarie sia la ripartizione che la formattazione. In caso contrario è [http://wiki.laptop.org/go/How_to_Damage_a_FLASH_Storage_Device raccomandato mantenere la formattazione di fabbrica] del dispositivo.
 
=== Come ripartizionare ===
 
{{admon/warning | ATTENZIONE | Questo cancellerà tutti i dati della chiavetta USB! Si prega di leggere ''attentamente'' le istruzioni sotto.}}
 
{{admon/note | Saltare se si usa il metodo da riga di comando | Se si intende usare lo strumento <code>livecd-iso-to-disk</code> documentato di seguito, è possibile saltare questo passaggio ed il prossimo ''Come formattare'' passando semplicemente i parametri {{command|--format}} {{command|--msdos}} e {{command|--reset-mbr}}}}
<!-- La formattazione msdos non è più quella predefinita. -->
 
Se il drive non è stato partizionato bene (o se si è insicuri), usare {{command|fdisk}} per ripartizionarlo.
 
Includere solo il nome del drive nel comando, non il numero della partizione.  '''''Assicurarsi di selezionare il disco corretto, si potrebbe rischiare di cancellare dati importanti!'''''  Controllare l'output di <code>df -h</code> per sicurezza. Ad esempio se la partizione sarà <code>/dev/sdb1</code>, allora:
<pre>
su -c 'fdisk /dev/sdb'
</pre>
Se <code>fdisk</code> non è installato, avviare il comando {{command| su -c 'yum install util-linux-ng'}}.  
 
La sessione d'output seguente da {{command|fdisk}} mostra le risposte da dare al prompt. La linea che inizia con <code>Last cylinder ...</code> si riferisce alla dimensione del drive quindi potrebbe differire da quella dell'esempio. Il comando <code>d</code> cancella una partizione esistente; il comando <code>n</code> crea una nuova partizione; il comando <code>t</code> ne imposta il tipo; <code>w</code> esegue materialmente le modifiche (in qualsiasi punto prima di avviare il comando ''w'' è possibile fermare ''fdisk'' senza fare alcuna modifica sul disco).
<pre>
Command (m for help): '''d'''
Selected partition 1
Command (m for help): '''n'''
Command action
e  extended
p  primary partition (1-4)
'''p'''
Partition number (1-4): '''1'''
First cylinder (1-960, default 1): '''↵'''
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-960, default 960): '''↵'''
Using default value 960
Command (m for help): '''t'''
Selected partition 1
Hex code (type L to list codes): '''6'''
Changed system type of partition 1 to 6 (FAT16)
Command (m for help): '''a'''
Partition number (1-4): '''1'''
Command (m for help): '''w'''
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: If you have created or modified any DOS 6.x
partitions, please see the fdisk manual page for additional
information.
Syncing disks.
</pre>
 
=== Come riformattare ===
 
{{admon/warning | ATTENZIONE | Questo cancellerà tutti i dati sul drive USB! Si prega di leggere ''attentamente'' le istruzioni sotto.}}
 
To finish, the partition must be formatted with an actual file system using {{command|mkfs.vfat}} as the root user.  Unmount the device before using {{command|mkfs.vfat}}.  In the below example, {{filename|/dev/USBPARTITIONNAME}} might be, for example, {{filename|/dev/sdb1}}.  '''''Be sure to select the correct partition; formatting destroys all data on it!'''''
 
<pre>
su -c 'umount /dev/USBPARTITIONNAME'
su -c 'mkfs.vfat -F 32 -n usbdisk /dev/USBPARTITIONNAME'
</pre>
 
If you don't have mkfs.vfat installed, run "yum install dosfstools" as root.
 
== Download an ISO ==
 
(If you intend to use the "Graphical" method below, with a supported Fedora release, you can skip this step.  The program will download the ISO for you.)
 
You can use BitTorrent or your web browser to download a bootable image, or ISO, which you will install on your USB drive.
 
Quick links:
* [http://fedoraproject.org/en/get-fedora Supported releases]
* [http://fedoraproject.org/get-prerelease Pre-releases] (Alpha and Beta; redirects to previous supported release during pre-Alpha phase)
* [http://alt.fedoraproject.org/pub/alt/nightly-composes/desktop/ Nightly test composes]
 
You are looking for a file with "Live" in the name, usually of the form {{filename|Fedora-<version>-<architecture>-Live-Desktop.iso}}.  For example, {{filename|Fedora-{{FedoraVersionNumber}}-x86_64-Live-Desktop.iso}} is the {{FedoraVersion|short}} release for 64-bit Intel-compatible CPUs. Be sure to choose the correct file for your architecture.  32-bit releases will generally run on 64-bit hardware, but will not be optimized.
 
These instructions will also work for [[Spins Custom|Custom Spins]] of Fedora Live ISO images, including those you make yourself with Revisor (a graphical tool), or LiveCD Creator (command-line tool used by Revisor).  (Pungi is a command-line tool you can use to create installable ISOs, but not Live ISOs.)
 
If you use a LiveUSB with data persistence, you can use the "yum update" method described below to get the latest daily Rawhide RPMs (mostly for testers and not everyday use) [https://bugzilla.redhat.com/show_bug.cgi?id=446935 except for the kernel].  See [[Releases/Rawhide]] for more information about daily builds.
 
The nightly test composes will be built from the [[Releases/Branched|Branched]] release when there is one, and from [[Releases/Rawhide|Rawhide]] when there is no Branched.
 
== Write the stick ==
 
=== Graphical Method - Windows or Fedora ===
 
Fedora USB sticks can be created in Windows and Linux using the [http://fedorahosted.org/liveusb-creator liveusb-creator] utility. Note that this utility is only capable of writing Live images. It is possible to write non-live images to a USB stick, but you must use one of the two command-line methods documented below.
 
For Windows using the following steps:
* Download liveusb-creator from [http://fedorahosted.org/liveusb-creator the site]
* Double click 'liveusb-creator'
 
If you are using Fedora, you can use Add/Remove Programs and search for ''liveusb-creator'', or use the command line:
<pre>
su -c 'yum install liveusb-creator'
</pre>
 
To start, run {{command|liveusb-creator}} on the command line, or on the GNOME menu, go to ''Applications -> System Tools -> liveusb-creator''.
 
To use the tool, simply select a Fedora release to download from the drop-down box at top-right (or select an ISO you have already downloaded using the ''Browse'' button at top-left), select the USB stick to which you wish to write the image from the ''Target Device'' drop-down box, and hit the ''Create Live USB'' button.
 
=== Command Line Methods ===
 
In the following examples, replace {{filename|/path/to/ISO}} with e.g. {{filename|Fedora-16-x86_64-Live-Desktop.iso}} or the full path to the ISO you downloaded, e.g. {{filename|/tmp/Fedora-16-x86_64-Live-Desktop.iso}}.
 
Replace {{filename|/dev/USBPARTITIONNAME}} with the appropriate partition name.  For example, {{filename|/dev/sdb1}} in the example above ("Check the size of your USB drive"). '''''Be careful to specify the correct device, or you may lose important data!'''''
 
Both of these methods work with all Fedora images, not just live images: you can use {{command|dd}} or {{command|livecd-iso-to-disk}} to write a Fedora DVD or network installation ISO to a USB stick. However, for Fedora 15, non-live images cannot be written using {{command|dd}}.
 
==== Using dd for a direct copy ====
 
{{admon/warning | CAUTION | This will erase all data on the USB drive!  Please read the instructions below ''carefully''.}}
 
You can simply use dd (or similar direct imaging tools for other operating systems) to write a Fedora ISO to USB, although the specialized tools have additional features like non-destructive writing and data persistence. dd will always destroy any other data on the target stick, and cannot provide a persistent environment.
<pre>
su -c 'dd if=Fedora-16-x86_64-Live-Desktop.iso of=/dev/sd''X'' bs=8M'
</pre>
Note that in this specific case you want the device name (e.g. /dev/sdb) not the partition name (e.g. /dev/sdb1).
 
An equivalent for Windows is the [http://www.chrysocome.net/rawwrite RawWrite for Windows tool]. It should be capable of writing Fedora images much as described above, but this is not regularly tested.
 
In Fedora versions prior to {{FedoraVersion|long|17}}, a DVD image written to a USB stick with dd or an equivalent tool will function as a network installation image unless a special kernel parameter is added on boot: it will be capable of performing an installation, but it will need to retrieve packages from network repositories, it will not be able to use the packages present on the stick. To allow the installer to find the packages present on the stick, use the [[Anaconda/Options#repo|anaconda ''repo='' parameter]], pointing to the USB stick by its device node, label or UUID. DVD images of {{FedoraVersion|long|17}} do not suffer from this limitation.
 
==== Using the {{command|livecd-iso-to-disk}} tool ====
 
The {{command|livecd-iso-to-disk}} is the most capable and often most reliable method of writing a Fedora ISO image to a USB stick, but can only reliably be used from within Fedora. It does not work in Windows and is not supported (and will usually fail) in non-Fedora distributions. Please use the liveusb-creator tool, dd (or an equivalent tool), or a third-party tool such as unetbootin on other operating systems. It is also not a good idea to try and write a new Fedora release using the version of {{command|livecd-iso-to-disk}} in a much older Fedora release: it is best to only use a release a maximum of two versions older than the release you are trying to write.
 
{{command|livecd-iso-to-disk}} is usually available in the /LiveOS directory of the Live CD .iso file. You may loop mount the .iso, and procede as below, assured that you are using the version intended for your image:
 
Make a mount point:
$ su -c "mkdir /tmp/live"
 
Mount the .iso filesystem on your mount point:
$ su -c "mount Fedora-16-x86_64-Live-Desktop.iso /tmp/live"
 
Confirm the availability of {{command|/LiveOS/livecd-iso-to-disk}}:
$ ls /tmp/live/LiveOS
 
If the {{command|livecd-iso-to-disk}} script is not listed, your will need to obtain it from another source.  Check if the livecd-tools RPM is installed with this command:
rpm -q livecd-tools
You will see the name of the RPM and a version number if it is installed, or no output if it is not installed.
 
If "livecd-tools" is not installed, install it using this command, or PackageKit:
$ su -c 'yum install livecd-tools'
 
Detailed usage information is available in the first pages of the [http://git.fedorahosted.org/git/?p=hosted/livecd;a=blob;f=tools/livecd-iso-to-disk.sh;hb=HEAD#l27 livecd-iso-to-disk script], which you can also see by running {{command|su -c 'livecd-iso-to-disk --help'}}. Basic examples follow.
 
To make an existing USB stick bootable as a Fedora image without deleting any of the data on it, make sure that the USB drive is not mounted before executing the following, and give the root password when prompted:
 
If {{command|livecd-iso-to-disk}} is available in the .iso filesystem,
$ su -c "/tmp/live/LiveOS/livecd-iso-to-disk Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
otherwise,
$ su -c "livecd-iso-to-disk Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
(See [[#Data persistence|Data persistence]] below for how to create Live USB devices with more than temporary storage of user files and settings.)
 
In case it is not possible to boot from a disk created with the method shown above, before re-partitioning and re-formatting, often resetting the master boot record will enable booting:
$ su -c "livecd-iso-to-disk --reset-mbr Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
 
{{admon/warning | CAUTION | The following method will erase all data on the USB drive!  Please read the instructions below ''carefully''.}}
If necessary, you can have {{command|livecd-iso-to-disk}} re-partition and re-format the target stick. This is similar to performing the manual re-partitioning and re-formatting steps described earlier in this guide. 
$ su -c "livecd-iso-to-disk --format --msdos --reset-mbr Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
 
=== UEFI boot of USB sticks ===
 
Whether a Fedora image written to a USB stick will be bootable natively via UEFI is a somewhat complex question which depends on the Fedora release, the type of image (live or non-live), and the method used to write it. The {{command|--efi}} parameter to the {{command|livecd-iso-to-disk}} tool attempts to make a stick written with that tool natively UEFI bootable.
 
As of {{FedoraVersion|long|17}}, all images written using the ''dd'' method should be UEFI-bootable, and all images written with {{command|livecd-iso-to-disk --format --reset-mbr --efi}} should also be UEFI-bootable. Use of {{command|--efi}} without {{command|--format}} and {{command|--reset-mbr}} can be considered a 'best effort', and may not produce a UEFI-bootable stick.
 
=== Data persistence ===
 
Data persistence means that your files and settings will remain even after you reboot your live system.  You can perform updates just like a regular installation to your hard disk, except that kernel updates require [[#Kernel updates|manual intervention]] and [[#limited overlay|overlay space may be insufficient]]. The primary use of this feature is booting a USB stick with your live image as well as the persistent changes. Note that you will need to have space on your target USB stick for the live image plus your overlay plus any other data you want on the stick.
 
Use the ''Graphical Method'' described above to do this easily. There is a graphical slider in the interface you can use to assign space on the target stick for persistent storage.
 
If using the {{command|livecd-iso-to-disk}} tool, add the {{command|--overlay-size-mb}} parameter to add a persistent data storage area to the target stick. For example:
<pre>
su -c "livecd-iso-to-disk --overlay-size-mb 512 Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
</pre>
 
where 512 is the desired size (in megabytes) of the overlay. The [[livecd-iso-to-disk]] tool will not accept an overlay size value greater than 2047 for VFAT, but for ext[234] filesystems it is only limited by the available space.
{{anchor|limited overlay}}
{{admon/note | Limited Lifetime of Persistent Overlay | One very important note about using the "primary" persistent overlay for system changes is that due to the way it's currently implemented (as a LVM copy-on-write snapshot), every single change to it (writes AND deletes) subtracts from its free space, so it will eventually be "used up" and your USB stick will no longer boot (see this [http://thread.gmane.org/gmane.linux.kernel.device-mapper.devel/14644 dm-devel discussion] and [http://wiki.sugarlabs.org/go/LiveOS_image#Overlay_recovery this page] for emergency recovery). Because of these limitations, it is advisable to use the system-level persistence sparingly, for configuration changes and important security updates only. For a truly persistent write-many (vs write-once) overlay, use the ''--home-size-mb'' option to create a home directory filesystem image for personal files. Unlike the primary system overlay image, the home.img can be re-used and loop mounted outside of the liveusb environment.}}
 
The persistent overlay status may be queried by issuing this command on the live system:
<pre>
dmsetup status live-rw
</pre>
The returned value may look like this:
<pre>
live-rw: 0 8388608 snapshot 42296/204800 176
</pre>
 
where the fraction after 'snapshot' for the logical volume is that of 512-byte sectors consumed in the overlay.
 
=== From a running Live CD/DVD/USB ===
 
If you are already running a live CD, DVD, or USB and want to convert that into a bootable USB stick, run the following command:
 
su -c "livecd-iso-to-disk /run/initramfs/livedev /dev/USBPARTITIONNAME"
 
: (For versions before Fedora 17, use {{Code|/dev/live}} instead of {{Code|/run/initramfs/livedev}}.)
 
 
== How to Boot a Live USB Drive ==
 
* Power off the computer.
* Plug the USB drive into a USB port.
* Remove all other portable media, such as CD, DVD, or floppy disks.
* Power on the computer.
* If the computer is configured to automatically boot off of the USB drive, you will see a screen that says "Automatic boot in 10 seconds..." with a countdown.
* If the computer starts to boot off the hard drive, you'll need to manually configure it to boot off the USB drive.
** Wait for a safe point to reboot safely.
** As the machine starts to reboot, watch carefully for instructions on which key to press (usually a function key or Escape) to enter the boot device selection menu, or "BIOS setup".  Press and hold that key.  If you miss the window of opportunity (often only a few seconds) then reboot and try again.
** Use the BIOS setup menu to put your USB drive first in the boot sequence.  It might be listed as a hard drive rather than a removable drive.  Each hardware manufacturer has a slightly different method for doing so.  '''Use caution!'''  Your computer could become unbootable or lose functionality if you change any other settings.  Though these settings can be reverted, you'll need to remember what you changed in order to do so.
** Save the changes, exit, and the computer should boot the Live USB drive.
 
== Problems and solutions ==
 
=== liveusb-creator problems ===
 
* Try the [http://fedorahosted.org/liveusb-creator/wiki/FAQ liveusb-creator FAQ].
* Bugs are tracked in [https://fedorahosted.org/liveusb-creator/ Trac] - see e.g. [https://fedorahosted.org/liveusb-creator/report/1 existing tickets].  Please [https://fedorahosted.org/liveusb-creator/newticket open a new ticket] if you encounter any problems that have not already been reported.
* The [https://fedorahosted.org/mailman/listinfo/liveusb-creator liveusb-creator mailing list] has [https://fedorahosted.org/pipermail/liveusb-creator/ archives] which may also be useful.
 
=== Partition isn't marked bootable! ===
 
If you get the following message, you need to mark the partition bootable.
<pre>
$ su -c "livecd-iso-to-disk Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
Partition isn't marked bootable!
You can mark the partition as bootable with
    $ /sbin/parted /dev/sdb
    (parted) toggle N boot
    (parted) quit
Cleaning up to exit...
</pre>
 
To mark the partition bootable, run parted, and use the 'toggle X boot' command. For example:
<pre>
$ parted /dev/sdb
GNU Parted 1.8.6
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print                                                           
Model: Imation Flash Drive (scsi)
Disk /dev/sdb: 1062MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End    Size    Type    File system  Flags
1      32.3kB  1062MB  1062MB  primary  fat16           
 
(parted) toggle 1 boot
(parted) print                                                   
Model: Imation Flash Drive (scsi)
Disk /dev/sdb: 1062MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
 
Number  Start  End    Size    Type    File system  Flags
1      32.3kB  1062MB  1062MB  primary  fat16        boot
 
(parted) quit                                                           
Information: Don't forget to update /etc/fstab, if necessary.           
</pre>
 
=== Partitions need a filesystem label! ===
 
If you get the following message, you need to label the partition.
<pre>
$ su -c "livecd-iso-to-disk Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
Need to have a filesystem label or UUID for your USB device
Label can be set with /sbin/dosfslabel
Cleaning up to exit...
</pre>
 
To label the partition:
<pre>
su -c "dosfslabel /dev/USBPARTITIONNAME LIVE"
</pre>
 
=== Partition has different physical/logical endings! ===
 
If you get this message from fdisk, you may need to reformat the flash drive, as described earlier in this guide.
 
=== MBR appears to be blank! ===
 
If your test boot reports a corrupted boot sector, or you get the following message, you need to install or reset the master boot record (MBR).
<pre>
$ su -c "livecd-iso-to-disk Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
MBR appears to be blank.
You can add an MBR to this device with
Cleaning up to exit...
</pre>
 
To install or reset MBR:
$ su -c "livecd-iso-to-disk --reset-mbr Fedora-16-x86_64-Live-Desktop.iso /dev/USBPARTITIONNAME"
 
=== Issues using other Linux distributions ===
Ubuntu and derivative Linux distributions have a usb-creator program similar to Live USB Creator. This ''does not work'' with Fedora ISO images, it silently rejects them. usb-creator requires the ISO to have a Debian layout, with a /.disk/info file and a casper directory. Do not attempt to use this utility to write a Fedora ISO image.
 
The livecd-iso-to-disk script is not meant to be run from a non-Fedora system. Even if it happens to run and write a stick apparently successfully from some other distribution, the stick may well fail to boot. Use of livecd-iso-to-disk on any distribution other than Fedora is unsupported and not expected to work: please use an alternative method described above.
 
== Testing Live Image on USB ==
 
You can test your Live Image on USB using QEMU as shown in the screenshot below.
 
[[Image:FedoraLiveCD_USBHowTo_usb_flash_with_qemu.png|thumb]]
 
For example, if your USB flash drive is {{filename|/dev/sdb}}, you could type the following commands:
<pre>
su -c 'umount /dev/sdb1'
qemu -hda /dev/sdb -m 1024 -vga std
</pre>
== Mounting a Live USB filesystem ==
 
You can use the [http://git.fedorahosted.org/git?p=hosted/livecd;a=blob_plain;f=tools/liveimage-mount;hb=HEAD '''''liveimage-mount'''''] script in the {{package|livecd-tools}} package to mount an attached Live USB device or other LiveOS image, such as an ISO or Live CD.  This is convenient when you want to copy in or out some file from the LiveOS filesystem on a Live USB, or just examine the files in a Live.iso or Live CD.
 
== Kernel updates ==
 
If you have [[#limited overlay|sufficient overlay space]] to accommodate a kernel update on a Live USB installation, the kernel and initramfs will be installed to the /boot directory.  To put these into service they must be moved to the /syslinux directory of the installation partition.  This is accessible from the running Live USB filesystem at either the /mnt/live or /run/initramfs/live mount point. The new initramfs (such as initramfs-3.3.2-6.fc16.x86_64.img) and kernel (such as vmlinuz-3.3.2-6.fc16.x86_64) should be moved to replace the /mnt/live/syslinux/initrd0.img and /mnt/live/syslinux/vmlinuz0 files, respectively.
* '''Note''': Beginning with Fedora 17, [[dracut]] no longer includes the dmsquash-live module by default. So one should include it in {{Code|/etc/dracut.conf}} with, for example,<br><pre># echo 'add_dracutmodules+=" dmsquash-live "' >> /etc/dracut.conf</pre>
 
The following commands will move the new kernel and initramfs files and create symbolic links to them, in case one later wants to perform a full install of the image to a hard disk. 
bootpath=run/initramfs/live/syslinux
# bootpath=mnt/live/syslinux
new=3.3.2-6.fc16.x86_64
 
cd /
mv -f boot/vmlinuz-$new ${bootpath}/vmlinuz0
mv -f boot/initramfs-${new}.img ${bootpath}/initrd0.img
&nbsp;
ln -fs -T ../${bootpath}/vmlinuz0 boot/vmlinuz-$new
ln -fs -T ../${bootpath}/initrd0.img boot/initramfs-${new}.img
 
== See also ==
[http://www.redhatmagazine.com/2007/11/07/i-am-fedora-and-so-can-you/ Red Hat Magazine | I am Fedora, and so can you!]
 
== References ==
 
* http://www.redhat.com/archives/fedora-test-list/2007-May/msg00308.html
* http://www.redhat.com/archives/fedora-livecd-list/2007-April/msg00029.html
 
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Latest revision as of 16:41, 19 May 2017