Computing

LIO -fb is the new SCSI Target for Debian. Previously, we maintained the LIO tools from the pre-fork upstream branch. But, with good reasons, we’ve now moved to the newer -fb (Free Branch).

As the maintainer for those pacakges, I have a local LIO setup. Overy the years, I’ve been tuning and using this setup with a bunch of SCSI clients. Now with the new -fb packages it was worrisome for me, on how to migrate (Note: migration is not supported by the Debian packages) my old setup to the new one.

Now that we prepare for the next Debian Stable release (Stretch), it is time to provide some updates on what the current state of some of the (storage related) packages in Debian is. This is not an update on the complete list of packages related to storage, but it does cover some of them.

REMOVALS

• iscsitarget - The iscsitarget stood as a great SCSI target for the Linux kernel. It seems to have had a good user base not just in Linux but also with VMWare users. But this storage target was always out-of-tree. With LIO having gotten merged as the default in-kernel SCSI Target, development on iscsitarget seems to have stalled. In Debian, for Stretch, there will be no iscsitarget. The package is already removed from Debian Testing and Debian Unstable, and nobody has volunteered to take over it.
• system-storage-manager - This tool intended to be a simple unified storage tool, through which one could work with various storage technologies like LVM, BTRFS, cryptsetup, SCSI etc. But the upstream development hasn’t really been much lately. For Debian Stable, it shouldn’t be part of it, given it has some bugs.
• libstoragemgmt - libstoragemgmt is a universal storage client-side library to talk to remote Storage Arrays. The project is active upstream. For Debian, the package is out-of-date and, now, also needs a maintainer. Unless someone picks up this package, it will not be part of Debian Stretch.

UPDATES

I am happy to announce the release of apt-offline 1.7.2. This has turned out in time for the next release of Debian, i.e. Debian Stretch.

A long standing cosmetic issue in CLI of the progress bar total item count has been fixed. There are also a bunch of other bug fixes, for which the specifics are present in the git logs.

Also, in this release, we’ve tried to catch-up on the Graphical Interface, adding the GUI equivalent of the features, that were added to apt-offline in the recent past.

Most GNOME users may be using one or more extensions for the GNOME Shell. These extensions allow extending functionality for the shell, or modify default behavior, to suit the taste of many users, who may want more than the default. Having flexibility to customize the desktop to ones personal need is a great feature, and the extensions help achieve them.

The GNOME Shell Extensions distribution mechanism is primarily through the web. I think they aspire to achieve something similar to Chrome’s Web Store. Up till recently, the ability to install those Shell Extensions was a) Through your distribution channel, where your distribution may have packaged some of the extensions. b) Through the Firefox web browser. GNOME Shell Extensions installation from the web, to most of what I’m aware of, until recently, only worked with Firefox browser.

Recently, we had the User-Mode Linux suite out of Debian, which included user- mode-linux, user-mode-linux-doc and uml-utilities package. We are happy that we were able to bring it back into the archvie quick, and hope to maintain it active.

For many who may not know about UML, here’s a discription from its website:

User-Mode Linux is a safe, secure way of running Linux versions and Linux processes. Run buggy software, experiment with new Linux kernels or distributions, and poke around in the internals of Linux, all without risking your main Linux setup.

User-Mode Linux gives you a virtual machine that may have more hardware and software virtual resources than your actual, physical computer. Disk storage for the virtual machine is entirely contained inside a single file on your physical machine. You can assign your virtual machine only the hardware access you want it to have. With properly limited access, nothing you do on the virtual machine can change or damage your real computer, or its software.

Most of the use cases mentioned here are achievable with Containers today. The big difference UML provides in, is with a separate kernel. UML is an implementation of Linux as an architecture of Linux itself. It supports x86 and x86_64 architecture. And given that it is the port of the kernel, you can do many of the tests and experiments of the regular kernel, safely inside a confined UML environment. As with other virtualization implementations, the limitation comes in if you are working on physical hardware.

I finally made full switch to SSL for my website. Thanks to [this](https://hblok.net/blog/posts/2016/02/24/lets-encrypt-tls-certificate- setup-for-apache-on-debian-7/) simple howto on Let’s Encrypt. I had to use the upstream git repo though. The Debian packaged tool, letsencrypt.sh, did not have enough documentation/pointers in place. And finally, thanks to the Let’s Encrypt project as a whole.

PS: http is now redirected to https. I hope nothing really breaks externally.

For Debian Jessie, the version of apt-offline available is: 1.5.1. This version has had some [issues](https://bugs.debian.org/cgi- bin/pkgreport.cgi?pkg=apt-offline;dist=unstable).

My very 1st backports is available in the form of [apt-offline 1.7 for ](https://packages.debian.org/source/jessie-backports/apt- offline)[Debian](https://packages.debian.org/source/jessie-backports/apt- offline) Jessie Backports. For Debian Jessie users, this should fix most of the issues.

Today is an auspicious day. For those who know (or follow) the Hindu religion will be familiar; Today is Maha Shivaratri

On this day, It is great delight for me to be able to release Laptop Mode Tools, version 1.69

This release adds on many bug fixes and some enhancements. There is a new module (disabled by default) for cpuhotplug. The release tarball also includes a basic PolicyKit file for convenience, that packagers can use for the Laptop Mode Tools Graphical Configuration Interface. Apart from the policykit file, the graphical invocation script has been slightly fine tuned to work under pkexec and sudo. Some defaults have been tuned based on user requests - This should improve in situations where your External USB Mouse/Keyboard used to suspend after idle time periods.

Having moved to a new place, now at times, I also have to deal with power outages. As heat increases, the power outages will be much longer and more frequent. So much, that UPS and Power Inverters run out. Such are ideal times to measure idle power consumption for my laptop.

Here’s what my default (and idle) OS looks like. It should be standard to most “typical” users. Some minor odds could be apport, dnsmasq, and maybe, tor. Also, thanks to systemd, there are some native services which are now converted to socket activation based ones. There’s also Laptop Mode Tools for userspace power savings. But huge thanks to Intel’s work in making the kernel more power efficient. With things like Runtime PM and Intel P-State , we can now define, default and aggressive power-savings modes, helping conserve more power.

I very recently met someone, and we had a good productive discussion on the features and (long standing) bugs of the Linux kernel. No doubt, Linux is the most featureful kernel in the market. Is also a lot appealing given its breadth of platform support.

Of that discussion we had, it led about Linux’s behavior in tighter stressed scenarios where there is a lot of contention among the core subsystems. From the conversation, I got the feedback that perhaps the issue is no more valid. My conclusion was I must have missed out on the fix because I haven’t really spent any Engineering Lab time in recent past.