Release Notes -
This release includes the packages from the Centrych upgrades repository. The notable changes with this release are:
As with previous Centrych releases, you do not need to download this disc if you have already downloaded and installed the system to your computer. Please refer to the upgrade notes for details on how to upgrade your system to 12.04.3.
Includes the following 4.11 packages;
The LTS enablement stacks, which includes the 3.5, 3.8, and soon to be released 3.11 kernel, present a unique problem for packages like
Unfortunately, the release included with 13.10, which is compatible with 3.11, does not build properly under the earlier kernels available with LTS. It also, mistakenly, includes the
The package included with Centrych has been modified to adaptively build across all LTS kernels. It has also been changed to hook the
This package uses a modified kernel selection routine that selects from multiple Centrych kernels in a preferred order for each CPU architecture as follows:
The non-Centrych kernels;
This tool and an underlying package,
This release was made in support of the LibreOffice recommendation that the recently released, and final update to the 4.0 series, 4.0.6, be used for "conservative" needs.
Unlike the 12.04.1a release, this release has both the Ubuntu and Centrych updates repositories active and comes with the following applications that were present in the Centrych updates repository at the time the disc was created:
The updates repository will continue to receive updated applications, with the exception of LibreOffice, which will only be updated according to the LibreOffice release notes.
This is a re-release of 12.04.1 with the following changes:
Live Session Desktop Profile
The UEFI and BIOS boot menus now provide the option of selecting the Xcentrych desktop profile for use with the live session. Booting to the UEFI menu occurs by default. To access the menu when booting with a BIOS-based system press any key while the logo at the bottom of your screen is visible.
If you elect to install the system to hard disk the current desktop profile will be used as the default profile.
Xfce Whisker Menu Plugin
This plugin has been added to the system, but it is not the default. You can add it to your desktop by right-clicking the panel and selecting Panel → Add New Items...
Note: This release is now positioned in-line with LibreOffice recommendations that the 3.6.7 release, which is the last of that series, be used for "extra conservative" needs. As such, this release is configured to only receive security updates. Both the Ubuntu and Centrych updates repositories are inactive by default in this release.
Desktop Optimized Kernels
Centrych provides two custom kernels that have been optimized for desktop use. The live DVD comes with the conservatively optimized desktop kernel. An experimental optimized kernel is also available that includes the BFS process scheduler, it can be selected during installation.
Both kernels also include the experimental BFQ I/O scheduler, which can be selected for use during installation.
Full Disk Encryption
The Centrych installer offers the ability to install the system with full disk encryption. Additionally, the front-end used by Centrych when using full disk encryption provides user-friendly prompts and status/error messages.
Full disk encryption is also available for UEFI enabled systems and can successfully enter/exit hibernation, (to the extent permitted by the hardware it is running on), as well.
Systems installed with full disk encryption can enable auto-login and have their password passed to their desktop via the Linux kernel key service to automatically unlock their GNOME keyring.
Quasi Two-Factor Authentication
Systems installed with full disk encryption and SSO can also add a removable flash drive, typically a USB thumb drive or SD card, for quasi two-factor authentication. Several read-only values in the device are combined with your login password to form a stronger LUKS passphrase for unlocking your encrypted drive(s).
The following fixes have been added for improved hardware compatibility in Centrych.
The startup handling of the keyring has been modified so that only the secrets component is activated when launching GNOME services. The GPG, SSH, and PKCS#11 components are now options that are individually activated in the Advanced tab of Xfce Settings → Session and Startup.
This allows for peaceful coexistence of the GNOME secrets keyring, the OpenSSH agent, and the GnuPG2 gpg-agent (optional install).
The live DVD includes several accessibility tools for people with physical and/or sensory impairment(s) with each tool associated with a hotkey for easy startup. For people who do not need these tools the installer provides an option to have them removed during installation.
If you are installing Centrych within a VMWare or VirtualBox virtual machine, the installer will also install the appropriate support software and make several configuration changes for optimal virtualized performance.
Centrych is committed to providing the latest upstream releases of important software as they become available.
Centrych uses a modified version of the Qt-based Ubiquity installer packaged with Kubuntu, those changes are:
The Unified Extensible Firmware Interface (UEFI) is the next generation of computer firmware intended to replace the Basic Input/Output System (BIOS) firmware that is present in all IBM PC-compatible computers. A modified UEFI is used with MacOS as well.
The Centrych Live DVD (amd64 version only) is capable of booting from a computer with UEFI enabled, and will install Centrych properly for EFI boot.
Centrych comes with a backported version of GRUB from the 13.04 (raring) release. It has also been patched so that graphics are enabled during boot. This is required in order to support the full disk encryption passphrase prompt during boot, or when restarting a hibernated system.
All guided partitioning methods and hibernation have been confirmed to work with amd64 compatible systems, but no testing has been performed on MacOS hardware that we are aware of.
LTS Enablement Stack
LTS Enablement Stack are point releases to support newer hardware via an updated kernel and X stack. Both must be installed at the same time.
Solid State Disks
Centrych provides several features that can improve the performance and extend the longevity of solid state disks (SSD), they are:
Enabling hibernation in Centrych will allocate sufficient disk space to support hibernation, and enable the Xfce panel menu item that is disabled by default.
Note: the installer will override this option if there is insufficient free disk available.
This is a ram-based filesystem that will dynamically grow and shrink as data is written to or deleted from it. If enabled, which is the default, the size assigned during installation is 50% of RAM + Swap partition size.
This Linux kernel module creates a ram-based, compressed filesystem. Centrych uses this filesystem as high-priority swap space that, because of compression, can increase the amount of total memory (real + virtual) available. It also provides a net performance gain since swapping to RAM is much faster than to hard disk, or even an SSD.
By default, Centrych creates a zRAM swap space that is sized to 50% of actual available memory up to a maximum of 2GB, although it can be configured to use a different amount and can also be disabled.
Centrych uses several methods to prevent installation of certain KDE packages and disables several services that would lead to instability if they were installed or enabled on your system.
Plymouth Details Package
An optional package can be installed to configure plymouth to display boot messages during start-up. The mountall package has also been modified so that filesystem check (fsck) operations are displayed properly with the plymouth details mode.
The Postfix MTA is configured for local-only email and Thunderbird will auto-configure your local mailbox on first use. Centrych also provides an optional package that includes several periodic security audits that will email summary reports to the root user (set to forward to the primary user by default during installation).
Certain restricted media format software must be installed separately because Centrych is unable to distribute them due to patent and/or copyright restriction. Unless they or commercially available alternatives are installed, the multimedia software installed in your system cannot play copy-protected DVDs, MP3 audio, Flash and other media formats.
Please refer to multimedia section of the Centrych help document for details on how to obtain and install this software.
Centrych comes with UFW firewall enabled and configured to block all incoming network traffic by default. Also included is an updated release of the Gufw firewall configuration tool.