= Subset Repositories (Fedora 7) =

== Creating the Base Repository ==

The base distribution repository is created in the same way as it's always been done
on the earlier distribution releases. The files can be located anywhere but for
the purposes of this article, the directory `/srv/nb/distros/fc7` is used as a base.

To support both 32-bit and 64-bit machines on the network, the ISO images for both the 32-bit and 64-bit
releases are needed. If you only need one architecture, skip the parts pertaining to the other architecture
(similarly if you're using ''ppc'', substitute `ppc` for `i386` or `x86_64` as appropriate).

The ISO images should be placed the repository area on the server that you are using, e.g.:
{{{
# mkdir -p /srv/nb/distros/fc7/os/i386/iso/
# cp F-7-i386-DVD.iso /srv/nb/distros/fc7/os/i386/iso/

# mkdir -p /srv/nb/distros/fc7/os/x86_64/iso/
# cp F-7-x86_64-DVD.iso /srv/nb/distros/fc7/os/x86_64/iso/}}}

Create mount points so that the ISO images can be loopback-mounted:
{{{
# mkdir /srv/nb/distros/fc7/os/i386/dvd/
# chcon -t mnt_t /srv/nb/distros/fc7/os/i386/dvd

# mkdir /srv/nb/distros/fc7/os/x86_64/dvd/
# chcon -t mnt_t /srv/nb/distros/fc7/os/x86_64/dvd}}}

Edit `/etc/fstab` and add entries for the DVD images to get them mounted at boot time:
{{{
/srv/nb/distros/fc7/os/i386/iso/F-7-i386-DVD.iso /srv/nb/distros/fc7/os/i386/dvd iso9660 _netdev,ro,loop,fscontext=system_u:object_r:public_content_t 0 0
/srv/nb/distros/fc7/os/x86_64/iso/F-7-x86_64-DVD.iso /srv/nb/distros/fc7/os/x86_64/dvd iso9660 _netdev,ro,loop,fscontext=system_u:object_r:public_content_t 0 0}}}
<!> Note that these are just single long lines for each ISO image

It should now be possible to mount the ISO image(s) by issuing the command:
{{{

# service netfs start}}}
It may seem strange to treat local loopback mounts as "network filesystems" but
this is the point during the boot process where loopback mounts get done.
Using `service netfs start` rather than plain `mount -a` checks that there are
no SELinux issues (the former runs confined by SELinux, the latter does not). The long-winded mount options in the `fstab` entries prevent SELinux objecting if you serve out the repository using `ftp`, `httpd`, `rsync` etc.

You can then use `createrepo` to build the repository metadata:
{{{
# cd /srv/nb/distros/fc7/os/i386
# createrepo .

# cd /srv/nb/distros/fc7/os/x86_64
# createrepo .}}}
/!\ Be careful with your directory hierarchy; it is important that the only RPM files that live in the `/srv/nb/distros/fc7/os/i386` etc. directory or anywhere underneath that directory are the RPMs from your DVD ISO (i.e. the ones in the `dvd/Fedora` directory); any other RPMs that may be present will also be found by `createrepo` and included in the repository, which is probably not what you want.

{i} `createrepo` is in the `createrepo` package on the media

== Using the Base Repository ==

Now to actually use the newly-created repository.
The object is pull packages that are available from the local repository from that repository, and get anything else from the Internet.

The first step is to create lists of the packages on the media (and hence in the local repository):
{{{
# cd /etc/yum

# ls /srv/nb/distros/fc7/os/i386/dvd/Fedora |
        awk '{ pkgname = $1; sub("-[^-]*-[^-]*$", "", pkgname); print "\t" pkgname }' |
        uniq > fedora-7-i386-dvd-pkgs.conf

# ls /srv/nb/distros/fc7/os/x86_64/dvd/Fedora |
        awk '{ pkgname = $1; sub("-[^-]*-[^-]*$", "", pkgname); print "\t" pkgname }' |
        uniq > fedora-7-x86_64-dvd-pkgs.conf}}}
This process creates a sorted list of the packages on each DVD ISO
(the lists are slightly different for each architecture), one per line,
indented with a tab character at the start of each line. The tab character
(or at least some form of leading space) is important for later use.

Next, you need to edit the `/etc/yum.repos.d/fedora.repo` file, which tells
`yum` where to get the base packages from. The first section of the file is
for the `[fedora]` repository and initially looks like this:
{{{
[fedora]
name=Fedora $releasever - $basearch
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/releases/$releasever/Everything/$basearch/os/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY}}}

Change the line:
{{{

enabled=1}}}
to:
{{{

enabled=0}}}

Then add the following two repository definitions at the top of the file:
{{{
[fedora-dvd]
name=Fedora $releasever - $basearch (local media)
baseurl=file:///srv/nb/distros/fc7/os/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

[fedora-everything]
name=Fedora $releasever - $basearch (network)
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/releases/$releasever/Everything/$basearch/os/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY
exclude=
include=file:///etc/yum/fedora-7-i386-dvd-pkgs.conf}}}
/!\ Change the `i386` on the last line to `x86_64` or whatever the architecture for the machine is - `$basearch` substitution doesn't work here.

This works by explicitly excluding from the `[fedora-everything]` repository
(the packages to be downloaded from the Internet) the list of all of the packages
available on the media; the list of packages created earlier and pulled in using the `include=` directive is treated as a continuation of the previous `exclude=` line.

You should now be able to test your setup by installing some package.
Packages on the media will be shown as coming from `fedora-dvd` and
other packages will be shown as coming from `fedora-everything`.

== Creating the Updates Repository ==

The object here is to create an updates repository that contains only updates
for the packages available on the original media. This will reduce the bandwidth
and disk space needed to maintain the mirror.

The tool to be used is `reposync`, which is part of the `yum-utils` package.

Create a mirror configuration file, `/etc/yum.repos.d/fedora-updates-mirror.repo`
(this uses the same trick with `include=` but this time to specify the list of wanted packages
rather than the list of packages to exclude):
{{{
[fedora-7-updates-subset-i386]
name=Fedora 7 - i386 - Updates Subset
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/updates/7/i386/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=updates-released-f7&arch=i386
includepkgs=
include=file:///etc/yum/fedora-7-i386-dvd-pkgs.conf
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora

[fedora-7-updates-subset-x86_64]
name=Fedora 7 - x86_64 - Updates Subset
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/updates/7/x86_64/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=updates-released-f7&arch=x86_64
includepkgs=
include=file:///etc/yum/fedora-7-x86_64-dvd-pkgs.conf
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora}}}
<!> It's a good idea to replace the `mirrorlist` entries with `baseurl` entries pointing to a fast, nearby mirror; 
not all mirrors are as up to date as each other, so with the `mirrorlist` you might find that one day's
`reposync` run removes the updates downloaded in the previous day's run.

Then create a script `updates-sync`, and put it somewhere in your `PATH`, such as `/usr/local/bin`:
{{{

#!/bin/bash

echo "Updating mirror of fedora-7-updates-subset-i386"
reposync -n -g -d -r fedora-7-updates-subset-i386 -p /srv/nb/distros/fc7 |
        grep -Ev "Skipping existing|%"
createrepo -q -d -C /srv/nb/distros/fc7/fedora-7-updates-subset-i386
echo ""

echo "Updating mirror of fedora-7-updates-subset-x86_64"
reposync -n -g -d -a x86_64 -r fedora-7-updates-subset-x86_64 -p /srv/nb/distros/fc7 |
        grep -Ev "Skipping existing|%"
createrepo -q -d -C /srv/nb/distros/fc7/fedora-7-updates-subset-x86_64
echo ""}}}
Skip the part for any architecture you're not interested in.
The `grep` command here reduces the volume of output from `reposync` whilst
leaving the interesting output alone (unlike the `-q` option of `reposync`).
Don't forget to make the script executable:
{{{

# chmod 755 /usr/local/bin/updates-sync}}}

To populate the repository (download the update packages), just run `/usr/local/bin/updates-sync`.
This will create repositories in directories
`/srv/nb/distros/fc7/fedora-7-updates-subset-i386` and
`/srv/nb/distros/fc7/fedora-7-updates-subset-x86_64` for `i386` and `x86_64` respectively.

== Using the Updates Repository ==

Edit the `/etc/yum.repos.d/fedora-updates.repo` file, which tells
`yum` where to get the update packages from. The first section of the file is
for the `[updates]` repository and initially looks like this:
{{{
[updates]
name=Fedora $releasever - $basearch - Updates
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/updates/$releasever/$basearch/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=updates-released-f$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora}}}

Change the line:
{{{

enabled=1}}}
to:
{{{

enabled=0}}}

Then add the following two repository definitions at the top of the file:
{{{
[updates-local]
name=Fedora $releasever - $basearch - Local Updates
baseurl=file:///srv/nb/distros/fc7/fedora-7-updates-subset-$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora

[updates-network]
name=Fedora $releasever - $basearch - Network Updates
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/updates/$releasever/$basearch/
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=updates-released-f$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora
exclude=
include=file:///etc/yum/fedora-7-i386-dvd-pkgs.conf}}}
/!\ Change the `i386` on the last line to `x86_64` or whatever the architecture for the machine is - `$basearch` substitution doesn't work here.

This works by explicitly excluding from the `[updates-network]` repository
(the packages to be downloaded from the Internet) the list of all of the packages
available in the local updates repository, which is the same as the list of packages available on the media.

You should now be able to test your setup by running `yum update`.
Packages in the local repository will be shown as coming from `updates-local` and
other packages will be shown as coming from `updates-network`.

== No/Slow Internet Connection? ==

Edit the configuration files:
 * `/etc/yum.repos.d/fedora.repo`
 * `/etc/yum.repos.d/fedora-updates.repo`

Change the line:
{{{
enabled=1
}}}
to:
{{{
enabled=0
}}}
for the network repositories and leave just the local repositories enabled by default.
You should then be able to use the package management tools whilst offline, though you may find that
things you'd like to install appear not to be available.

To enable the Internet repositories for a single `yum` run whilst you're online, use:
{{{
# yum --enablerepo=fedora-everything --enablerepo=updates-network update
}}}
or
{{{
# yum --enablerepo=fedora-everything --enablerepo=updates-network install somepackage
}}}
etc.
----
CategoryTip