Difference between pages "Cloud Backup" and "Package:XDM (Display Manager)"

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(remove layman stuff. its in the repo already)
 
m (my bad...)
 
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This howto will describe a method for automatically backing up your funtoo install to the internet, in this case dropbox, but any online storage will do. Gentoo describes a method of creating a stage 4 archive. The problem with a stage 4 is that it is large and it archives a lot of unnecessary files. Such as applications that can be reinstalled from an emerge world. Instead, this method will aim for more of a "stage 3.5."
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{{Ebuild
 +
|Summary=X.Org xdm application
 +
|CatPkg=x11-apps/xdm
 +
|Maintainer=
 +
|Homepage=http://www.freedesktop.org/wiki/display_manager/
 +
}}
 +
==install==
 +
<console>###i## emerge xdm</console>
  
{{fancynote| This method does not attempt to backup everything. The intention is only to backup the system. Optionally you can also archive and copy your <tt>/home</tt> folder if you have enough online storage.}}
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==configure==
 +
xdm is controlled by <code>/etc/conf.d/xdm</code>.
  
== Use Case ==
+
xdm is often paired with other, more modern display managers.
A backup machine currently provides network drives on a home LAN to allow clients on the LAN to backup to, using apps such as Time Machine (Mac) and Genie Timeline (Windows). As this machine ''is'' the backup machine it doesn't have anywhere to backup to itself. In this situation a backup solution is provided by backing up to somewhere online - dropbox. If a restore from the backup is required, the client machine's backups would be trashed, and the backup machine restored.
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see:
 +
*{{package|lightdm}}
 +
*{{package|gdm}}
 +
*{{package|kdm}}
 +
*{{package|slim}}
  
== Automatic Backup Archives With Etckeeper ==
+
==init==
Etckeeper is a tool that is used to save versions of <tt>/etc</tt>, including meta-data in a version control repository such as git. Install it via:
+
to start xdm immediately:
 +
<console>###i## rc-service xdm start</console>
  
<console>
+
to start xdm upon boot:
###i## emerge etckeeper
+
<console>###i## rc-update add xdm</console>
</console>
+
{{EbuildFooter}}
 
+
== Configure etckeeper ==
+
Move any config files that do not live in <tt>/etc</tt>. i.e.
+
Check <tt>/root</tt> for any files to be archived, such as iptables scripts, and move them to <tt>/etc</tt>.
+
 
+
{{fancynote| because funtoo uses [[Boot-Update]], this means that <tt>/boot/grub/grub.cfg</tt> does not need to be archived.}}
+
 
+
To ensure your portage world file is archived, make the following link:
+
<console>
+
###i## ln /var/lib/portage/world /etc/world
+
</console>
+
 
+
Initialize the git repository:
+
<console>
+
###i## etckeeper init
+
Initialized empty Git repository in /etc/.git/
+
###i## etckeeper commit "Initial commit."
+
</console>
+
 
+
If you don't already have a cron daemon installed, emerge one now:
+
<console>
+
###i## emerge vixie-cron
+
</console>
+
 
+
{{fancynote| git will only create a new version (commit) if there are changes from the previous one.}}
+
Write a cron job to save an hourly version of <tt>/etc</tt> by creating the file <tt>/etc/cron.hourly/etckeeper</tt>:
+
 
+
<syntaxhighlight lang="bash">
+
#! /bin/bash
+
etckeeper commit "Hourly auto-commit"
+
</syntaxhighlight>
+
 
+
== Encrypt and copy backups online ==
+
=== Copy To Dropbox ===
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<console>
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###i## emerge dropbox
+
</console>
+
 
+
Add a dropbox user:
+
<console>
+
###i## useradd dropbox
+
</console>
+
 
+
Write the dropbox init files in <tt>/etc/conf.d/dropbox</tt>:
+
<syntaxhighlight lang="bash">
+
#!/sbin/runscript
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# Copyright 1999-2004 Gentoo Foundation
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# Distributed under the terms of the GNU General Public License, v2 or later
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# $Header: /var/cvsroot/gentoo-x86/sys-fs/dropbox/files/dropbox.init-1.0,v 1.4 2007/04/04 13:35:25 cardoe Exp $
+
 
+
DROPBOX_USERS="dropbox"
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NICENESS=5
+
 
+
depend() {
+
    need localmount net
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    after bootmisc
+
}
+
 
+
start() {
+
    ebegin "Starting dropbox..."
+
    for dbuser in $DROPBOX_USERS; do
+
        start-stop-daemon -S -b -m --pidfile /var/run/dropbox-$dbuser.pid  -N $NICENESS -u $dbuser -v -e HOME="/home/$dbuser" -x /opt/dropbox/dropboxd
+
    done
+
    eend $?
+
}
+
 
+
stop() {
+
    ebegin "Stopping dropbox..."
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    for dbuser in $DROPBOX_USERS; do
+
        start-stop-daemon --stop --pidfile /var/run/dropbox-$dbuser.pid
+
    done
+
    eend $?
+
}
+
 
+
status() {
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    for dbuser in $DROPBOX_USERS; do
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        if [ -e /var/run/dropbox-$dbuser.pid ] ; then
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            echo "dropboxd for USER $dbuser: running."
+
        else
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            echo "dropboxd for USER $dbuser: not running."
+
        fi
+
    done
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    eend $?
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}
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</syntaxhighlight>
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Start dropbox now and at boot time:
+
<console>
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###i## chmod 0755 /etc/init.d/dropbox
+
###i## /etc/init.d/dropbox start
+
###i## rc-update add dropbox default
+
</console>
+
 
+
After starting the dropbox daemon, it will provide a http link. You will need to visit this site just once to associate your computer with your dropbox account.
+
 
+
Write the cron job to make the backup archive and move it online. Create the file <tt>/etc/cron.daily/backup</tt>:
+
<syntaxhighlight lang="bash">
+
#! /bin/bash
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cd /etc
+
git bundle create /tmp/backup.bundle --all
+
cd /tmp
+
mv -v -f backup.bundle /home/dropbox/Dropbox/Private/
+
</syntaxhighlight>
+
 
+
Make the script executable:
+
<console>
+
###i## chmod +x /etc/cron.daily/backup
+
</console>
+
 
+
=== Encrypt Backups ===
+
It is a good idea to encrypt your backup before moving it online. This can be done with gpg, using a symmetric (password only) or public/private key encryption. Additionally you can chose to sign the backup to check its integrity before restoring.
+
<console>
+
###i## emerge gpg
+
</console>
+
 
+
==== Symmetric Encryption ====
+
There is no preparation required to use a symmetric key as all that is required is simply a passphrase.  Just modify the cron job. Edit <tt>/etc/cron.daily/backup</tt>:
+
 
+
<syntaxhighlight lang="bash">
+
#! /bin/bash
+
cd /etc
+
git bundle create /tmp/backup.bundle --all
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cd /tmp
+
echo 'encryption_password' | gpg -o backup.gpg --batch --homedir /root/.gnupg -vvv  --passphrase-fd 0 --yes -c backup.bundle
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mv -v -f router.gpg /home/dropbox/Dropbox/Private/
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</syntaxhighlight>
+
{{fancyimportant| Remember to change <tt>encryption_password</tt>}}
+
{{fancywarning| If you forget this password the backup will be unusable. Lose the password and you lose the backup.}}
+
 
+
As there is now sensitive information in this file, you might want to remove read permission:
+
<console>
+
###i## chmod og-r /etc/cron.daily/backup
+
</console>
+
 
+
==== Private/Public key Encryption ====
+
Make a private/public encryption/decryptions key pair. The public key will be used to encrypt and the private key to decrypt.
+
<console>
+
###i## gpg --gen-key
+
</console>
+
The public key is used to create the encrypted backup and needs to live on the computer being backed up. A copy of the private key needs to be made and stored securely in another place. If this machine becomes unbootable, and this is the only place the private key lives, the backup dies with it.
+
The private key should not be kept:
+
* In the same place as the back up
+
* On the machine being backed up
+
{{fancynote| The private key is the only key that will decrypt the backup. Lose this key and/or it's password and you lose the backup.}}
+
 
+
List the private keys:
+
<console>
+
###i## gpg -K
+
/root/.gnupg/secring.gpg
+
------------------------
+
sec  2048R/0EF13559 2012-01-21
+
uid                  my_key <noone@example.com>
+
ssb  2048R/67417FEB 2012-01-21
+
</console>
+
 
+
The private key can be exported using either the key name or key number. In this case "my_key" or "0EF13559".
+
To cut and paste the key. Ie, if logging in remotely.
+
<console>
+
###i## gpg -a --export-secret-key 0EF13559
+
</console>
+
 
+
To create a key file:
+
<console>
+
###i## gpg -o private_decryption.gpgkey --export-secret-key 0EF13559
+
</console>
+
 
+
Now store this key somewhere secure. The backup is only as secure as the private key.
+
 
+
Modify the cron job at <tt>/etc/cron.daily/backup</tt>:
+
 
+
<syntaxhighlight lang="bash">
+
#! /bin/bash
+
cd /etc
+
git bundle create /tmp/backup.bundle --all
+
cd /tmp
+
gpg -o backup.gpg -r 'my-key' --batch --homedir /root/.gnupg -vvv  --passphrase-fd 0 --yes -e backup.bundle
+
mv -v -f backup.gpg /home/dropbox/Dropbox/Private/
+
</syntaxhighlight>
+
 
+
{{fancynote| Replace "my-key" with the appropriate name from the key list. Also note the change from -c for symmetric encryption to -e for private/public key encryption. }}
+
 
+
==== Sign Backups ====
+
Create a 2nd private/public (signing) key pair. The private key is used to sign and the public key is used to check the authenticity/integrity.
+
<console>
+
###i## gpg --gen-key
+
</console>
+
 
+
{{fancynote| The password for this key will be required in the script below.}}
+
In this case the private key is required to sign the backup and the public key is used to check the integrity of the backup.
+
Follow a similar process as above to copy the public key to to another computer/storage media.
+
 
+
List the private keys:
+
<console>
+
###i## gpg -k
+
</console>
+
{{fancynote| <tt>-K</tt> lists private keys while <tt>-k</tt> lists public keys.}}
+
 
+
Then export this public key via cut and paste:
+
<console>
+
###i## gpg -a --export <key name or number>
+
</console>
+
 
+
Or to create a key file:
+
<console>
+
###i## gpg -o public_signing.gpgkey --export <key name or number>
+
</console>
+
 
+
Now store this key somewhere secure.
+
 
+
Modify the backup cron job at <tt>/etc/cron.daily/backup</tt>:
+
 
+
<syntaxhighlight lang="bash">
+
#! /bin/bash
+
cd /etc
+
git bundle create /tmp/backup.bundle --all
+
cd /tmp
+
echo 'signing_key_password' | gpg -s -o backup.gpg -r 'my-encryption-key' --batch --homedir /root/.gnupg -vvv  --passphrase-fd 0 --yes -e backup.bundle
+
mv -v -f backup.gpg /home/dropbox/Dropbox/Private/
+
</syntaxhighlight>
+
 
+
{{fancynote| the script will require the password for your private (signing) key to sign the backup. Replace "password" with the password for your signing private key.
+
And as there is sensitive information in this file don't forget to remove read permission.}}
+
<console>
+
###i## chmod og-r /etc/cron.daily/backup
+
</console>
+
 
+
== To Restore From A Backup ==
+
This restore will assume your are starting with a new blank disk.
+
Start by performing a stage 3 install, upto and including section 5 "Chroot into your new system." http://www.funtoo.org/wiki/Funtoo_Linux_Installation
+
 
+
Then the restore process is:
+
# Download backup from dropbox
+
# Decrypt
+
# Clone
+
# Link world file
+
# Emerge world
+
# Compile the kernel
+
# Restore grub bootloader
+
# Reboot
+
 
+
== Download backup from dropbox ==
+
Log into your dropbox account and find your backup file. Move it to a public area if it isn't already in one. Then right click on it and click "copy public link."
+
Now on the computer to be restored, delete the contents of the /etc folder and download the backup file.
+
 
+
(Need to check if this needs done before chrooting into the new install).
+
<console>
+
###i## cd /etc
+
###i## rm -rf *
+
###i## cd /tmp
+
###i## wget http://dl.dropbox.com/link-to-backup-file/backup.gpg
+
</console>
+
 
+
{{fancynote| if you have to copy the link from another computer and therefore can not cut and paste it, there is a "shorten link" option.}}
+
 
+
== Decrypt ==
+
If you used a public/private key to encrypt, and optionally signed the backup, import the decryption and signing keys.
+
 
+
Note:
+
# The decryption key is the private key of the encryption key pair - private_decryption.gpgkey
+
# The signing key is the public key of the signing key pair - public_signing.gpgkey
+
 
+
To import the keys by cut and paste:
+
<console>
+
###i## gpg --import <<EOF
+
</console>
+
{{fancynote| The last line after pasting the key should be "EOF"}}
+
Repeat for both keys.
+
 
+
To import the keys by file:
+
<console>
+
###i## gpg --import private_decryption.gpgkey
+
###i## gpg --import public_signing.gpgkey
+
</console>
+
 
+
Decrypt the backup:
+
<console>
+
###i## gpg -d backup.gpg > backup.bundle
+
</console>
+
 
+
If the backup was signed and you have correctly imported the signing public key you should see a message similar to:
+
<console>
+
gpg: Good signature from "my_signing_key <noone@example.com>"
+
</console>
+
 
+
== Clone ==
+
<console>
+
###i## git clone /tmp/backup.bundle /etc/
+
</console>
+
 
+
== Link world file ==
+
<console>
+
###i## ln /etc/world /var/lib/portage/world
+
</console>
+
 
+
== Emerge world ==
+
<console>
+
###i## emerge --sync
+
###i## layman -S
+
###i## emerge -uDaNv world
+
</console>
+
 
+
== Compile the kernel (genkernel)==
+
If you have genkernel set to save config files (the default):
+
<console>
+
###i## cp /etc/kernels/kernel-config-x86_64-<latest version>-gentoo /usr/src/linux/.config
+
</console>
+
 
+
Otherwise use the currently loaded kernel's config:
+
<console>
+
###i## zcat /proc/config.gz > /usr/src/linux/.config
+
</console>
+
 
+
Then compile the kernel:
+
<console>
+
###i## genkernel --oldconfig --no-mrproper all
+
</console>
+
 
+
== Restore grub bootloader ==
+
<console>
+
###i## grub-install --no-floppy /dev/sda
+
###i## boot-update
+
</console>
+
 
+
Adjust the device as required if installing to another location.
+
 
+
== Reboot ==
+
<console>
+
###i## reboot
+
</console>
+
 
+
[[Category:First Steps]]
+
[[Category:HOWTO]]
+

Revision as of 01:46, October 26, 2014

x11-apps/xdm


Source Repository:Gentoo Portage Tree
Homepage

Summary: X.Org xdm application

Use Flags

consolekit
Enable native sys-auth/consolekit support
xdm-auth
Enable XDM-AUTHENTICATION-1 support

XDM (Display Manager)

install

# emerge xdm

configure

xdm is controlled by /etc/conf.d/xdm.

xdm is often paired with other, more modern display managers. see:

init

to start xdm immediately:

# rc-service xdm start

to start xdm upon boot:

# rc-update add xdm