Frequently Asked Questions
- What is a
CD image
anyway? - My question is not answered by this FAQ!
- Why should I use this
jigdo
program? I prefer a simple HTTP download! - Which of the numerous images should I download? Do I need all of them?
- What is a
netinst
ornetwork install
CD? - What are the
update
USBs/CDs/DVDs? - What are the
source
CDs? - Where is the CD image with non-free?
- What's the difference between official and unofficial images?
- Is a Debian
live image
available? - The USB/CD/DVD/BD fails to boot! / From which disc should I boot?
- Where are the images for M68K, Hurd or other architectures?
- Are images for the
unstable
distribution available? - Which USB/CD/DVD/BD image contains package XYZ?
- Can I have a list of all the packages contained in an image?
- The software on the official CDs is outdated - why don't you release a new version?
- How do I know if I am downloading the newest images?
- How can I verify the downloaded ISO images and written optical media?
- Why is my downloaded DVD image smaller than 1 GB when it should be larger than 4 GB?
- How do I write an ISO image under Linux/Unix?
- How do I write an ISO image under Windows?
- How do I write an ISO image under Mac OS?
- How do I write a USB/CD/DVD/BD image to a USB flash drive?
- How do I write a USB/CD/DVD/BD image on Windows to a USB flash drive?
- How should I label the discs?
- Are old USB/CD/DVD/BD images still available?
- What is the best way of installing Debian on many interconnected computers?
- I have a local Debian mirror and want to create my owns USBs/CD/DVDs/BDs. How do I do this?
- How do I become a mirror for Debian USB/CD/DVD/BD images?
- Some Images are missing! Only the first n images are available! Where is the rest?
A CD image is the exact representation of the data on a CD in a normal computer file, that can e.g. be transmitted over the Internet. CD burning programs can use the image files to make real CDs.
In Debian, we use the term CD image
as a common way to
describe a range of things, many of which don't even fit on CD! The
name is old, but it has stuck. We regularly build multiple different
types of image:
- Debian installer images in multiple sizes. These range from
small CD-sized
netinst
images for quick download up to large complete sets of images designed for DVD, Blu-Ray (BD) or Dual-Layer Blu-Ray (DLBD) media. - Debian live images - live systems designed to be run directly from USB/CD/DVD without needing installation. See below for more details.
In many cases, these installer and live images can often be written
directly to USB flash drives with no CD involved;
see below. Don't be put off by the name CD
image
!
For a correctly written image, the .iso file must not
appear on the media when you access it! Instead, you should see a
number of files and directories - in the case of a Debian installer
image, this includes a
dists
directory and a README.html
file.
The .iso format we use for our images is roughly
comparable to a .zip file: It contains other files and
directories, and only these will appear on the final USB/CD/DVD
medium. Some archive programs allow you to unpack
.iso files. Do not use this feature to create a USB/CD/DVD from the
unpacked files! The resulting medium will fail to boot because the
.iso format includes special information related to booting
from the USB/CD/DVD, which is lost when you unpack the file. See below on how
to correctly write a CD/DVD image under Linux,
Windows or Mac
OS, or how to write an image to a USB flash
drive.
My question is not answered by this FAQ!
If you cannot find an answer to your question here, you can ask for help on one of the Debian mailing lists. In all cases, you should search the mailing list archives before sending mail to the lists. You can subscribe to and unsubscribe from the lists. However, you do not need to be subscribed in order to send mail to the lists - if you are not subscribed, ask for replies to be CC'd to you.
Mailing lists relevant to problems with CD installation:
- debian-cd: Discussion about the CD image creation process, available CD mirrors, problems when booting from CD, announcements of new official images.
- debian-boot: A bit of a misnomer, this list actually covers the installation process; any problems encountered after successfully booting from CD may be more appropriate here than in debian-cd.
- debian-live: A list for the Debian Live project, focused on development of the software that is used to build Debian Live images, but also appropriate for discussion particular to using those images.
- debian-user: General support list for users of Debian. Focus is more on problems encountered after a successful installation, when using the system. There are also several lists for non-English speakers, in Català, Chinese, Dansk, Esperanto, Français, Deutsch, Magyar, Indonesian, Italiano, 日本語 (Nihongo), Polski, Português, Русский (Russkij), Español, Svenska, Türkçe, and Ukrainian.
Why should I use this jigdo
program?
I prefer a simple HTTP download!
Today, there are nearly 300 Debian mirrors (which contain the complete Debian distribution as .deb files), and machines serving Debian CD images.
Additionally, nobody is very enthusiastic about setting up more
CD servers because of the tremendous amounts of wasted bandwidth
(some people keep restarting failed downloads instead of
resuming from the point where the connection was closed)
and because a regular mirror is more attractive (it allows
continuous upgrades of Debian, or using the testing
/unstable
distribution instead of the stable
one).
jigdo tries to make the most out of this situation, by downloading the data for the CD images from one of the 300 mirrors. However, these mirrors only hold individual .deb files, not the CD image, so some additional manipulation of the data is necessary to produce one big CD image file from the many small .deb files.
Do not be afraid to try out jigdo! The complex process of generating the CD image is completely hidden from you - instead, you benefit from the fact that one of the 300 Debian mirrors is bound to be nearer and faster than any of the CD servers.
Which of the numerous images should I download? Do I need all of them?
No. First, of course you only need to download CD or DVD or BD images - the three types of images contain the same packages.
Also, you only need the USB/CD/DVD/BD images for your computer's
architecture. The architecture is the type of hardware your computer
uses. By far the most popular one is the 64-bit Intel/AMD PC
architecture, so most people will only want to get the images
for amd64
. If your PC has an older 32-bit AMD or Intel
processor, you will most likely need the
i386
images instead.
Furthermore, in most cases it is not necessary to download all of the images for your architecture. The packages are sorted by popularity: The first USB/CD/DVD/BD contains the installation system and the most popular packages. The second one contains slightly less popular ones, the third one even less popular ones, etc. You will probably only need the first couple of DVDs (or the first BD, etc.) unless you have very special requirements. (And in case you happen to need a package later on which is not on one of the USBs/CDs/DVDs/BDs you downloaded, you can always install that package directly from the Internet.)
Please also read the next paragraphs to determine whether you want/need to download network install CDs, update CDs or source CDs.
What is a netinst
or network install
CD?
To quote the network install page: A
network install
or netinst
CD is a single CD which enables you to
install the entire operating system. This single CD contains just the
minimal amount of software to install the base system and fetch the
remaining packages over the Internet.
If you only want to install Debian on a single machine which has a fast Internet connection, the network install may be the fastest and easiest option for you: You only download the packages that you selected for installation on your machine, which saves both time and bandwidth.
What are the update
USBs/CDs/DVDs?
Update USBs/CDs/DVDs are USBs/CDs/DVDs which contain all the packages that
changed between a major release version (e.g. 7.0,
8.0, etc.) and a later point release of that stable
distribution. For example, if you already have the full set of
debian-8.0.0
USBs/CDs/DVDs, you can add the
debian-update-8.2.0
disc set to turn this debian-8.0.0
set into a debian-8.2.0
set.
This type of USB/CD/DVD is intended for vendors having large amounts of pressed versions of USBs/CDs/DVDs (which makes them cheaper than individually burned USBs/CDs/DVDs). If you order USBs/CDs/DVDs from such a vendor, it is possible that you'll receive USBs/CDs/DVDs for a slightly older point release, plus some update USBs/CDs/DVDs for the latest revision. This is a perfectly acceptable way of distributing Debian on USB/CD/DVD.
Of course, this type of USB/CD/DVD can also be useful to you as an end user; instead of creating the full set of USBs/CDs/DVDs for each new revision of a release, you only need to download and burn update USBs/CDs/DVDs for your architecture.
Note that update USBs/CDs/DVDs are not meant to boot, they just contain the
packages needed to upgrade an existing installation. If you don't have
that existing installation, then you'll need to use the normal
installation USBs/CDs/DVDs. After the new system is booted, the updated
USB/CD/DVD can be added with apt-cdrom add
.
Now, what if for some reason you do not want to download the update
USB/CD/DVD even though you already have the full set of USBs/CDs/DVDs/BDs for
the previous revision? In this case, you should consider using jigdo's update
feature: jigdo can read
the contents of the old USBs/CDs/DVDs/BDs, download only those files that
have changed for the new USBs/CDs/DVDs, and create the full set of new
USBs/CDs/DVDs/BDs. Still, it will have done this by downloading only about
the same amount of data as for an update USB/CD/DVD.
There are two types of images, the binary
CDs that contain
precompiled, ready-to-run programs, and the source
CDs that
contain the source code for the programs. The vast majority of
people do not need the source CDs; you should not download them
unless you really have a good reason for it.
Where is the CD image with non-free?
Debian has a quite strict view with regard to the licenses of
software: Only software that is Free in the sense of the
Debian Free Software
Guidelines is allowed into the actual distribution. All the other,
non-free
software (for example, software for which source code is not
available) is not supported officially.
The official CDs may freely be used, copied and sold by anyone anywhere
in the world. Packages of the non-free
category have restrictions that
conflict with this, so these packages are not placed on the official
CDs.
Sometimes, someone is kind enough to create unofficial non-free CDs. If you cannot find any links on this website, you can try asking on the debian-cd mailing list.
What's the difference between official and unofficial images?
Official images are built by a member of the Debian CD team and have undergone some testing to ensure they work. Once they have been released, the images never change - if they turn out to be broken, a new set with a different version number is released.
Unofficial images can be built by anyone - CD team members, other Debian developers or even advanced Debian users. Typically, they are more up-to-date, but have received less testing. Some have new features (e.g. installation support for new hardware), or contain additional software packages which are not part of the Debian archive.
Is a Debian live image
available?
Yes. A so-called live image
(live CD
), or more
precisely, a live system
, is a complete system prepared for a
DVD, USB key or other medium. You do not need to install anything on
the hard drive. Instead you boot from the medium (DVD or USB key) and
are able to start working on the machine right away. All programs run
directly from the medium.
The Debian Live Project produces live image files for a variety of system types and media.
The USB/CD/DVD/BD fails to boot! / From which disc should I boot?
Only the first USB/CD/DVD/BD in a set is bootable.
If your Debian disc fails to boot, first ensure that you have correctly written it to the medium - please see the explanation above. Additionally, please check whether your BIOS is set up to boot from your optical or USB drive.
Where are the images for M68K, Hurd or other architectures?
Depending on the state of support for a certain architecture, USB/CD/DVD images are available from different places:
- If the architecture you are looking for is officially
supported by the current stable
release, see the
Debian on CD
page for the available download options. - If a Debian port for an architecture exists, but has not
yet been released officially, CD images may or may not be
available. Again, see the
Debian on CD
page - in contrast to stable images, only one download option may be supported, so have a look at both thejigdo
andHTTP
sections. - For the Debian port to the GNU/Hurd, see the page about unofficial Hurd CDs.
- Otherwise, check the Debian port pages for the architecture you are interested in.
Are images for the unstable
distribution available?
There are no unstable
full USB/CD/DVD/BD images. Due to the fact
that the packages in unstable
change so quickly, it is more
appropriate for people to download and install unstable
using a
normal Debian HTTP mirror.
If you are aware of the risks of running unstable, but still want to install it, you have a few choices:
- Install
testing
using a netinst image, then upgrade tounstable
by changing the entries in your /etc/apt/sources.list. To avoid unnecessary downloads and package upgrades, it is advisable to install a minimaltesting
system first and only to install most of the software (e.g. desktop environment) after the switch tounstable
. - Use the stable installer to install a minimal
stable
system and then change your /etc/apt/sources.list file to usetesting
and do an apt-get update and apt-get dist-upgrade. Finally, install the packages you desire. This method is the most likely to work of those presented here. - Be a tester of the
testing
installer and installtesting
using a netinst image, then upgrade tounstable
by changing the entries in your /etc/apt/sources.list. To avoid unnecessary downloads and package upgrades, it is advisable to install a minimaltesting
system first and only to install most of the software (e.g. desktop environment) after the switch tounstable
. Then apt-get update and apt-get -u dist-upgrade - then you have a sid release. - Use a netboot
mini.iso
image. You will find it on any of the Debian mirrors under debian/dists/unstable/main/installer-*/current/images/netboot/mini.iso. During the installation chooseAdvanced options
->Expert install
. In the stepChoose a mirror of the Debian archive
choose versionsid - unstable
.
Which USB/CD/DVD/BD image contains package XYZ?
To find out which image contains a certain file, use the cdimage search tool. It has knowledge of just about all the Debian USBs/CDs/DVDs/BDs produced by Debian since the 3.0 (Woody) release, covering all the official releases (both older archived releases and the current stable release) and the current sets of daily and weekly testing builds.
Can I have a list of all the packages contained in an image?
Yes. Look on cdimage.debian.org for the corresponding .list.gz file - it will list all the packages and source files included in the image. For Debian Live images, you can find in the same directory as the image files some similarly named files suffixed with .packages. Download these and then search them for the desired package name.
The software on the official CDs is outdated - why don't you release a new version?
We only make official releases of the stable
distribution
when we think they truly deserve that name. Unfortunately, this means
that stable releases only happen about every 2 years...
If you require more recent versions of some of the software in
Debian, you can install stable
and then upgrade (via the net)
those parts you want to the versions from testing
- it is
possible to mix software from the different releases.
Alternatively, try out the images of testing
that are
generated automatically every week. More information about testing
security support
is available from the security FAQ.
If you only need newer versions of specific packages, you can also
try the backports
service, which takes packages from testing
and modifies them to work on stable. This option may be safer than
installing the same package directly from testing.
How do I know if I am downloading the newest images?
The note at the bottom of the Debian on CD
page
always shows the version number of the latest
release.
How can I verify the downloaded ISO images and written optical media?
Detailed information on how to authenticate the signed checksum files containing the checksums of the ISO image files is available on the authenticity verification page. After cryptographically verifying the checksum files, we can check that:
- Checksums of the downloaded ISO image files match those
found in the checksum files. Computing the checksum of the ISO image
files is performed by tools such as
sha512sum
andsha256sum
. - Checksums of already written optical media match those found in the checksum files. This is a slightly more difficult operation to describe.
The problem with the verification of written optical media is that some media types will possibly return more bytes than those found in the ISO image. This trailing garbage is impossible to avoid with CD written in TAO mode, incrementally recorded DVD-R[W], formatted DVD-RW, DVD+RW, BD-RE, and also with USB keys. Therefore, we need to read exactly the same number of sectors of data from the media as are found in the ISO image itself; reading any more bytes from the media will alter the checksum result.
- The
isosize
program can be used to find out the appropriate amount of bytes to be read from the optical media. It shows thesector count
and thesector size
from the optical media, where<device>
is the device file of the loaded optical media.
$ /sbin/isosize -x <device>
sector count: 25600, sector size: 2048 - Then
sector count
andsector size
are passed todd
to read the appropriate amount of bytes from the optical media and the byte stream is then piped to the appropriate checksum tool (sha512sum, sha256sum, etc).
$ dd if=<device> count=<sector count> bs=<sector size> | sha512sum - The computed checksum is to be compared against the corresponding checksum found in the appropriate checksum file (SHA512SUMS, SHA256SUMS, etc).
Alternatively, there is a useful helper script called check_debian_iso which can verify ISO image files and optical media, reading the appropriate amount of bytes from media then computing the checksum and comparing it against the checksum file.
- ISO image file verification.
This will compare the checksum of the debian-6.0.3-amd64-netinst.iso
image file against the corresponding checksum found in the SHA512SUMS
checksum file.
$ ./check_debian_iso SHA512SUMS debian-6.0.3-amd64-netinst.iso - Optical media verification.
This will compare the checksum of the media accessible as /dev/dvd against the
checksum of debian-6.0.3-amd64-DVD-1.iso as found in the SHA512SUMS
checksum file. Note that the ISO image file itself is not needed,
its name is merely used to locate the corresponding checksum in
the checksum file.
$ ./check_debian_iso SHA512SUMS debian-6.0.3-amd64-DVD-1.iso /dev/dvd
Why is my downloaded DVD image smaller than 1 GB when it should be larger than 4 GB?
Most likely, the tool you use for downloading the image does not have large file support, i.e. it has problems downloading files larger than 4 GBytes. The usual symptom for this problem is that when you download the file, the file size reported by your tool (and the amount of data that it downloads) is too small by exactly 4 GB. For example, if the DVD image is 4.4 GB, your tool will report a size of 0.4 GB.
Some old versions of wget also suffer from this problem -
either upgrade to a version of wget which does not have this
restriction or use the curl command line download tool:
curl -C - [URL]
How do I write an ISO image under Linux/Unix?
Note that Debian ISO images for i386, amd64 and arm64 are also bootable from a USB key; see below.
xorriso
for all optical media types (also doable as non-root user):
xorriso -as cdrecord -v dev=/dev/sr0 -eject debian-x.y.z-arch-MEDIUM-NN.iso
In order to get the full nominal speed when writing to BD-RE
(i.e. without the slowdown caused by the drive's internal defect
management), add the option stream_recording=on.
growisofs
for DVD and BD optical media types:
growisofs -dvd-compat -Z /dev/sr0=debian-x.y.z-arch-MEDIUM-NN.iso
wodim
for CD optical media type:
wodim -v dev=/dev/sr0 -eject -sao debian-x.y.z-arch-CD-NN.iso
For Linux, there are also the X programs Brasero, K3B and X-CD-Roast, to name a few. Note that they're all frontends to the previously mentioned low-level burning applications.
- Brasero
- Select the button Burn Image. Then click on Click here to select a disc image, browse and select your downloaded ISO file, check whether the settings under Properties are correct and choose Create Image.
- K3b
- Select the menu entry Tools - CD - Burn CD Image. In the dialog that opens, enter the path to the image in the Image to Burn field, check whether the other settings are correct, then click on Start.
- X-CD-Roast
- After the program has started, click on Setup and choose the HD settings tab. Copy the Debian CD image to one of the directories that are displayed in the table. (If the table is empty, enter the path of a directory you want to use for temporary storage, and click on Add.) Click on OK to exit the setup. Next, select Create CD and then Write Tracks. Choose the Layout tracks tab, select the line displaying the image filename and click on Add, then click on Accept track layout. Finally, click on Write tracks.
How do I write an ISO image under Windows?
On recent versions of Windows, this can be done natively by right-clicking the ISO and selecting "Burn image to disk (or similar)"
This might be a little problem on older versions of Windows, as
many Windows image-burning programs use their own formats for CD
images. To burn the .iso images you will most likely have to
use a special
menu. Look for options like ISO9660 file
,
Raw ISO image
or 2048 bytes/sector
. (Note: other
bytes/sector values are fatal!) Some programs do not offer these
choices; use another burning program instead (ask a friend or
colleague). Here is some information about how to write CD images with
specific products:
- ImgBurn (Freeware)
- There are screenshots of how to write an image to CD/DVD
- CDBurnerXP Pro (Freeware)
- The process of writing an .iso image is described in the program's manual.
- Roxio Easy-CD Creator
- From the File menu, choose Create CD from
image.... Then select the
.iso
file type, and the correct image. This opens up the CD creation setup GUI, from there ensure that all the information for your CD-R is correct. In the Create options portion, choose Create CD; under Write method, choose Track at once and Close CD. - Nero from Ahead Software
- Disable the Wizard, then select Burn Image from the
File
orRecorder
menu. Select All Files in the file selection window if necessary. Select the .iso file, click OK in thethis is a foreign file
dialogue box, in case one is displayed. In the option box that opens, the defaults should be okay:Data Mode 1
,Block Size 2048
,Raw Data, Scrambled, and Swapped
not selected, and Image Header and Image Trailer left at 0. Click OK. Under Write CD or Burn, use the default options, e.g. Write and Determine maximum speed, plus check the Finalize CD option. - Microsoft Resource Kit Tools
- The command-line Resource Kit Tools are provided by Microsoft free of charge, they work with Windows 2003 and XP. Two programs to write images to CD and DVD are included, they are named Cdburn.exe and Dvdburn.exe. Usage of the programs is described in the accompanying help file - essentially, the command to be executed is something like cdburn drive: iso-file.iso /speed max
If you can provide updated information or details for other programs, please let us know.
How do I write an ISO image under Mac OS?
The Toast program for Mac OS is reported to work fine with .iso files. You can be extra-safe by giving it the creator code CDr3 (or possibly CDr4) and type code iImg using e.g. FileTyper. Double-clicking on the file will then open up Toast directly, without having to drag-and-drop or go via the File-Open menu.
Another option is Disk Utility (included with Mac OS X 10.3 and higher): After opening the Disk Utility application (in the /Applications/Utilities folder), select Burn... in the Image menu and choose the CD image to burn. Ensure that the settings are correct, then click on Burn.
Another option is Disk Copy (included with Mac OS X 10.1 and higher): After opening the Disk Copy application (in the /Applications/Utilities folder), select Burn Image... in the Image menu and choose the CD image to burn. Ensure that the settings are correct, then click on Burn.
How do I write a USB/CD/DVD/BD image to a USB flash drive?
Several of the Debian and Debian Live images, notably all i386, amd64 and arm64 images, are created using the isohybrid technology, which means that they may be used in two different ways:
- They may be written to CD/DVD/BD and used as normal for CD/DVD/BD booting.
- They may be written to USB flash drives, bootable directly from the BIOS / EFI firmware of most PCs.
On a Linux machine, simply use the cp
command, to copy an
image to a USB flash drive:
cp <file> <device>
Alternatively you can also use dd
:
sudo dd if=<file> of=<device> bs=16M status=progress oflag=sync
where:
- <file> is the name of the input image, e.g.
netinst.iso
. - <device> is the device matching the USB flash drive, e.g. /dev/sda, /dev/sdb. Be careful to make sure you have the right device name, as this command is capable of writing over your hard disk just as easily if you get the wrong one!
status=progress
outputs the current progress of the operation in your terminal.oflag=sync
flushes the cache so the operation is really finished when the command succeeds, the USB flash drive can be removed right after the command is finished.
Please note, that Debian advises not using unetbootin
for
this task. It can cause difficult-to-diagnose problems with booting
and installing, so is not recommended.
How do I write a USB/CD/DVD/BD image on Windows to a USB flash drive?
For Windows users we recommend to use balenaEtcher.
- There's a version of balenaEtcher that can be used without installing it onto your computer.
- Just download balenaEtcher-portable.exe and open/execute it.
- If there's a security warning, confirm that you want to open balenaEtcher.
- Then select an ISO file, select the target device (your USB stick), finaly flash. That's it.
There is no obligatory way of labeling. However, we suggest you use the following scheme to ensure interchangeability:
Debian GNU/{Linux|Hurd}
<version>[<revision>]
Official
{<architecture>} {CD|DVD|BD}-<number>
For example:
Debian GNU/Linux 6.0.3
Official i386
CD-1
Debian GNU/Linux 6.0.3
Official
amd64 DVD-2
Debian GNU/Linux 6.0.3
Official
source BD-1
Debian GNU/Hurd 6.0.3
Official i386
Netinst CD
If you have enough space, you can also add the codename to the
first line, as in: Debian GNU/Linux 6.0.3 Squeeze
.
Note that you are allowed to use the Official designation only on CDs the image of which has a checksum that matches the one from the jigdo files of official releases. Any CD that has no matching checksum (e.g. your own creations) must be clearly labelled as Unofficial, for example:
Debian GNU/Linux 6.0.3
Unofficial
Non-free
In the case of official weekly snapshots, version numbers like
6.0.3
should not be used to avoid confusion with released
Debian versions. Instead, label the image with a codename like
etch
or a distribution name like testing
. Also add
Snapshot
and the date of the snapshot to help identify it:
Debian GNU/Linux etch
Official Snapshot alpha Binary-2
2005-06-17
Are old USB/CD/DVD/BD images still available?
Some older images are available from the archive section on cdimage.debian.org. For example, you might want to try out older images if you need support for a certain (sub)architecture which has been dropped for a newer release.
Note that when you install using a really old USB/CD/DVD (pre 4.0, Etch), the contents of /etc/apt/sources.list will reference the current stable Debian release by default. This means that any upgrade over the net will upgrade to the current stable release.
What is the best way of installing Debian on many interconnected computers?
If you want to install Debian on a large number of machines and then keep all these installations up-to-date (e.g. security updates), installing from optical media is not ideal, but then neither is installing via the Internet, because the packages will have to be downloaded again for each machine. In this case, you should set up a local cache, the three options being:
- Make disc contents available via HTTP: Download the
images, then make their contents available to your LAN on a local
mirror. The individual machines can use this mirror as if it
were a regular Debian server. For example, if the contents of a CD
are available under the URL http://10.0.0.1/cd1/, machines
in the local network can use the packages from the CD with the
following line in their /etc/apt/sources.list:
deb http://10.0.0.1/cd1/ stable main contrib
A different URL and a separate entry in sources.list is necessary for each CD. - Instruct your HTTP proxy to cache .deb files:
Configure the proxy to keep .deb files for a long time, then set
http_proxy in your environment on each machine to point
at the cache, and use apt's HTTP acquisition method.
This gives you most of the benefits of running a mirror, with none of the admin hassle. Since you can set limits on the proxy's disk usage, it works even for sites with limited disk space, and it has the advantage over mirroring that you only download those packages you install, which saves bandwidth. Squid can be told to keep the files by adding a line to /etc/squid/squid.conf:
refresh_pattern debian.org/.*.deb$ 129600 100% 129600 - Set up a private Debian packages mirror: Beware that the Debian archive has grown to a tremendous size! Refer to the mirroring page for details.
Installing on a large number of machines can be tricky. Fully automatic installation (FAI), provides a web service for creating customized installation images, that may help you with this task.
I have a local Debian mirror and want to create my owns USBs/CD/DVDs/BDs. How do I do this?
Apart from a local Debian mirror, you also need plenty of disc space. The image creation scripts are packaged in the debian-cd package. However, it is usually a better idea to use the latest code from git. (Still, you should have a look at the package's dependencies to ensure you have all the necessary tools.)
To get the latest git version, make sure you have git installed. From an empty directory, give the following command:
git clone https://salsa.debian.org/images-team/debian-cd.git
Should you try to use the scripts, check the debian-cd mailing list archive for solutions to the questions that will inevitably show up. :-)
How do I become a mirror for Debian USB/CD/DVD/BD images?
The necessary steps to set up your debian-cd image mirror and keep it up to date are described on a separate page.
Some Images are missing! Only the first n images are available! Where is the rest?
We don't store/serve the full set of ISO images for all architectures, to reduce the amount of space taken up on the mirrors. You can use the jigdo tool to recreate the missing ISO images instead.