Usage tips and tricks

Use TurnKey Core to apply and develop patches

While you can install tklpatch on any system that has the required dependencies we recommend using TurnKey Core in a VM if possible because it is verified to work. Different versions of the tklpatch's dependencies on other systems (e.g., Gentoo) may behave a bit differently and break things. Also this way you can avoid issues created by conflicts between servers on your development box (e.g., MySQL or PostgreSQL) and the patch chroot.

Updating the configuration console usage text

The recommended way is to use the overlay, as its simpler than tweaking the file using something like sed, and less error prone. The confconsole usage template is located at:

/etc/confconsole/usage.txt

Configuring a custom hostname

It's a nice touch to set a custom hostname that is more specific to the appliance being created:

HOSTNAME=newname
echo "$HOSTNAME" > /etc/hostname
sed -i "s|127.0.1.1 \(.*\)|127.0.1.1 $HOSTNAME|" /etc/hosts

Enabling a repository (ie. component)

If there is a need to enabled a repository that is currently disabled by default (such as multiverse), it can be done like this:

APT_SOURCES=/etc/apt/sources.list.d
sed -i "/hardy multiverse/ s/# //" $APT_SOURCES/sources.list

# note, you might also want to uncomment updates and security
sed -i "/hardy-updates multiverse/ s/# //" $APT_SOURCES/sources.list
sed -i "/hardy-security multiverse/ s/# //" $APT_SOURCES/security.sources.list

Preseeding a Debian package

Preseeding provides a way to set answers to questions asked during the package installation process, without having to manually enter the answers while the installation is running. This makes it possible to fully automate package installation.

The following example would accept license of the sun-java6 packages:

debconf-set-selections << END
sun-java6-jdk shared/accepted-sun-dlj-v1-1 boolean true
sun-java6-jre shared/accepted-sun-dlj-v1-1 boolean true
sun-java6-bin shared/accepted-sun-dlj-v1-1 boolean true
END

Inithooks

A simple initialization mechanism built into all TurnKey appliances. What it does is provide the means to run various configuration and initialization scripts on first boot.

http://code.turnkeylinux.org/inithooks/docs/README

You want each instance to have a unique set of secret keys (e.g., SSH, SSL). You also want to have a way to set passwords for various accounts.

If you're installing a TurnKey appliance via the Live CD build target then there's an interactive installer that can do that for you, but in a VM deployment scenario you don't have an installer - so to get around
that inithooks is configured to trigger these installer hooks on first boot.

Currently we are including the following hooks:

    /usr/lib/inithooks/firstboot.d/
        20live-installer    - executes the live-installer scripts
        30rootpass          - sets the root password
        30mysqlpass*        - sets the mysql root password
        30pgsqlpass*        - sets the pgsql postgres password

* - only included in appliances when relevant

For example, here's what the firstboot scripts look like for the TurnKey
LAMP appliance::

    $ cd /usr/lib/inithooks/firstboot.d
    $ ls
    20live-installer  30mysqlpass  30rootpass

    $ cat 20live-installer
    #!/bin/sh

    . /etc/default/inithooks
    . $INITHOOKS_PATH/functions

    exec_scripts /usr/lib/live-installer.d

    $ cd /usr/lib/live-installer.d
    $ ls
    20regen-sshkeys  25regen-sslcert  40regen-pmapass  90unset_firstboot

    export ROOTPASS=p4ssw0rd
    export MYSQLPASS=myp4ss
    export PGSQLPASS=pgp4ss

    cat > /usr/lib/inithooks/firstboot.d/99cleanup<<EOF
    #!/bin/sh
    rm -f /etc/inithooks.conf
    EOF
    chmod +x /usr/lib/inithooks/firstboot.d/99cleanup

Functions (for use with tklpatch .92+)

install()
    {
        apt-get update
            DEBIAN_FRONTEND=noninteractive apt-get -y \
            -o DPkg::Options::=--force-confdef \
            -o DPkg::Options::=--force-confold \
            install $@
    }

#args: file_to_extract, destination
#ex: install_targz /tmp/MyApp.tar.gz /usr/share/myapp
install_targz()
    {
        tar zxvf $1 -C /tmp
        mkdir $2
        mv /tmp/$(tar tf $1 | head -1)/* $2
        rm -r /tmp/$(tar tf $1 | head -1)
    }

cleanup_apt()
    {
        rm -r /var/cache/apt/*
        mkdir /var/cache/apt/archives
        mkdir /var/cache/apt/archives/partial
    }