Category Archives: Stiri IT Externe

New LibreOffice Version Offers Fresh Take | Software

By Jack M. Germain

Aug 9, 2018 10:54 AM PT

The Document Foundation on Wednesday announced the availability of its second major release this year, LibreOffice Fresh 6.1, with enhanced editing on Desktop, Cloud and Mobile platforms.

New LibreOffice Version Offers Fresh Take

One of its most significant new features is Notebookbar, an improved experimental user interface option that resembles the ribbon interface popular with Microsoft Office users.

The developers hope to release a fully refined ribbon-style interface in the next major release, according to Italo Vignoli, spokesperson for the foundation.

The Fresh release targets both early adopters and power users. Early adopters are mostly individual users. Power users are those participating in enterprise deployment of the open source office suite.

LibreOffice Notebookbar

(Click Image to Enlarge)

The 6.1 release is the start of a new development cycle for LibreOffice. The office productivity suite has undergone a four-part development cycle starting with code cleaning in version 3.x, continuing with code refactoring in version 4.x, improving the user interface in version 5.x and enhancing ubiquitous productivity in this current release.

“LibreOffice 6.1 represents the bleeding edge in terms of features for open source office suites,” Vignoli told LinuxInsider.

It is built with document conversion libraries from
The Document Liberation Project.

The new features were developed by a large community of code contributors. Almost 72 percent of commits are from developers employed by companies sitting in the Advisory Board, including Collabora, Red Hat and CIB Software, and by other contributors, including SIL and Pardus.

LibreOffice Google Trends

What’s New

The top new features include two new icon styles and a revamped image handling system. Also, much attention has been given to aligning features for consistency among the five office modules.

“Krasa Jaga” — a new icon style that replaces a Linux font style no longer maintained — means “looking to the future” in Indonesian.

The Colibre icon style is designed to provide the look and feel of Windows 10. It is based on Microsoft’s icon design guidelines, which makes the office suite visually appealing for users coming from the Microsoft environment.

Developers extensively reworked the way LibreOffice 6.1 handles images with a completely new and much improved graphic manager, improved lifecycle handling, deprecation of accessing embedded images by URL, and on-demand loading of images from OOXML and MSO formats.

The image handling process is now more functional, according to Vignoli. It eliminates issues caused by using too many images in a document.

“The old handling methods were not entirely proficient in handling the software with images. Many LibreOffice users do not fully understand how to apply images on a page. They make a lot of mistakes,” he said.

The changes make users’ lives easier. Image handling is now more stable and easier to use. Pages with lots of images load much more quickly than before.

More Improvements

Improvements and feature upgrades extend to all LibreOffice modules in this release. Aligning the features is a major push in version 6.1, according to Vignoli.

Developers redesigned the database engine in the Base module to make it more user-friendly, he said. The changes are a work in progress and are considered experimental. They will be refined for version 6.2.

The reorganization of Draw menus comes with the addition of a new Page menu. This results in a better user experience consistency across the different modules.

LibreOffice Draw Menus and Styles

A major improvement for Base is available only in experimental mode. The old HSQLDB database engine has been deprecated, but it is still available.

The new Firebird database engine is now the default option. A migration assistant helps users migrate files from HSQLDB to Firebird. Another option is to export them to an external HSQLDB server.

An improved EPUB export filter gives better performance to link, table, image, font embedding and footnote support. More options now exist for customizing metadata.

Online Help pages have been enriched with text and example files to guide users through features. Also, they now are easier to localize.

The features are aligned in all of the modules for improved ease of use.

Almost Like (Ribbon) Heaven

The improved but still experimental Notebookbar feature is similar in style to the Windows ribbon interface, but it is not meant to be identical, said Vignoli.

“It is under development more as a transition for Microsoft Office users to give them a more familiar style UI,” he said. “We would like Office users switching to LibreOffice to have a familiar interface.”

The developers deliberately chose not to call the feature a “Windows-style ribbon” interface, Vignoli said. It has a different background. It is created to look in a way that is similar — but there are distinct differences.

For one thing, the new UI does not take the same amount of space as the Microsoft ribbon interface, he pointed out. It is limited in size. Designers are working on reducing the vertical face of the Notebookbar.

So far, the Notebookbar interface is more suitable for smaller laptop screens. Developers want it to be equally functional on desktops.

“It is still evolving, so it is introduced as experimental. We hope to make it a fully developed feature with the next major release, version 6.2,” Vignoli said.

Established Stability

The Document Foundation has been playing it coy with the way it addresses the concept of stability in LibreOffice. That is part of the rationale behind calling this latest release the “Fresh” version. It named the previous release, version 6.1, “Still.”

The Still version is more suitable for larger enterprise deployment, as it has been tested by more people, Vignoli acknowledged.

However, “after eight years, LibreOffice is quite stable with a large organization of volunteers and company-sponsored developers,” he pointed out. “After eight years of developing LibreOffice, we have shown that stability is not an issue anymore.”

Caution is in order, however, based on how enterprises deploy major software platforms, noted TDF Director Thorsten Behrens, who has been a senior developer with the project since OpenOffice, and also serves as LibreOffice Team Leader at
CIB, which provides value-added document services.

“Some companies really do not want to upgrade every half year or yearly,” Behrens told LinuxInsider.

In previous years, performance issues and feature limitations were tied to the speed of the user’s CPU. The amount of memory in the user’s machine also was a performance variant.

“Those criteria essentially no longer exist. LibreOffice just works,” Behrens said.

That said, for any enterprise class deployment, TDF recommends the more mature LibreOffice 6.0, according to Vignoli. The software should be sourced from a company that provides a Long Term Support version of the suite.

Built-In Code Corrections

The Document Foundation spent years cleaning up code using
Coverity Scan to reduce and then eliminate the number of errors that otherwise would contribute to stability issues, according to Vignoli. That has had a major impact on making LibreOffice both stable and secure.

For example, the most recent code scan on July 20 showed that for nearly 6.5 million lines of code the defect density detected was zero, he pointed out. The analysis chart shows that over the last few years LibreOffice code went from a defect density of 0.02 in 2016 to 0.0 since January of this year.

“So we are definitely a lot better. This goes to show not only the quality of LibreOffice code but also the amount of work on quality and security matters of the source code provided by our developers,” said Vignoli.

Every week there is a new scan on code development. Developers take care of whatever faults are found in the source code a long time before they get to the consumers as binary code, he added.

Online Version More Challenging

Developers have been furthering their efforts to improve all modules of LibreOffice Online, incorporating changes to the user interface to make it more appealing and consistent with the desktop version.

The online engine is exactly the same, so the features have become more aligned. The eventual goal is to offer online version users the same range of features the desktop version offers, gradually introducing them during the next two or three major releases.

Unlike Google Docs and Microsoft Office online products, LibreOffice Online is not available for everyone to use for free. LibreOffice Online is fundamentally a server service and should be installed and configured by adding cloud storage and an SSL certificate.

LibreOffice online now has more features, making it similar to the standalone version. However, the online version is available only to users with access to ISPs or enterprise servers that offer it as a feature.

No Plans for Online Catch-Up

Having a fully functional online version that equals the functionality of the desktop version is *not* in the works, Vignoli emphasized. The Document Foundation lacks the finances and infrastructure to provide an online version the likes of Google Docs and Office Online.

However, developers have been adding features to the online version and improving its look and feel. Numerous issues with using the online version have been resolved for a better user experience.

ISPs can provide the online version for a monthly fee or for free. Also, enterprises can provide it on their own servers. However, the foundation can not provide it to everyone. Some enterprise cloud-sharing services, such as NextCloud, provide access to the LibreOffice online version.

A better online option to overcome restricted access to the online version of LibreOffice would be improved mobile support on Android devices, Vignoli suggested.

The Android LibreOffice Viewer app has been getting more support. It now can provide some editing as well as file display functionality.

However, support for LibreOffice on the Chrome OS is not in the works. Vignoli suggested that using LibreOffice Viewer on a Chromebook that supports Android apps could be one possible workaround.

That approach typically would not provide access to local storage on Android devices, though. Users would need to figure out how to work around documents stored in the cloud or use a method that Android apps on Chrome OS can access.

Mixed Views on Using LibreOffice

Whether LibreOffice is a suitable free replacement for Microsoft Office depends on several factors, according to Charles King, principal analyst at Pund-IT. It might not be universally ideal for both individuals and power users.

For example, if an organization has standardized on Linux, then LibreOffice is a solid option that is bolstered by its free cost and integration with Google Cloud for backup, file sharing, and so forth.

“It should also be an adequate option for power users, especially those who are interacting with other LibreOffice users,” King told LinuxInsider.

That is mainly due to complaints about incompatibilities between LibreOffice and Word, due to Microsoft using its own version of OOXML, he explained. So users working with Word docs may be better off by purchasing a Microsoft license. For most businesses, those users are a minority of employees.

Weighing the Options

Potential LibreOffice adopters should consider possible downsides, urged king. With more than two decades into the “revolution” sparked by Linux and open source solutions, LibreOffice still constitutes a small fraction of the productivity applications and tools market.

Would that be the case if these offerings really were superior? Adopting any new platform requires retraining, and that includes LibreOffice, he said. Most employees arrive knowing at least the rudiments of Word and other Microsoft apps.

Plus, to its credit, Microsoft has addressed many user complaints and Office 365 makes it cheaper and easier to use the company’s solutions than ever before, added King.

“So companies have to sort out why they are considering LibreOffice,” he suggested, to determine “what potential benefits are actually achievable and whether leaving behind a longtime market leading solution (Office) really makes sense.”

Jack M. Germain has been an ECT News Network reporter since 2003. His main areas of focus are enterprise IT, Linux and open source technologies. He has written numerous reviews of Linux distros and other open source software.
Email Jack.

Source link

Opera Embraces Snap for Linux » Linux Magazine

Ubuntu’s Snap is gaining popularity. After Microsoft, now Opera is backing Snap packaging format to distribute their apps to Linux platform. Opera may not be one of the most popular browsers today, but they did a lot of innovation back then, including tabs, saved sessions, pop-up blocking, and speed dial. Opera and Canonical, the parent company of Ubuntu, worked together to bring Opera web browser to Linux a Snap.

“The addition of Opera to the Snap Store enables users of all major Linux distributions to benefit from the auto-updating and security features that Snap provides. The Opera Snap is supported on Debian, Fedora, Linux Mint, Manjaro, Elementary, OpenSUSE, Ubuntu and more distributions,” Canonical said in a press release.

“We are delighted to welcome Opera to the Snap Store and further expand the choice of applications available to the Linux community. It is popular applications, such as Opera, that have driven the impressive growth of new Snaps to the store and ever-increasing user installs over the last year,” added Jamie Bennett, VP of Engineering, IoT and Devices at Canonical.

To those who don’t know, Snaps are containerized software packages, inspired by Docker containers, that are designed to offer isolation as well as fully self-contained packages that don’t rely on system libraries and dependencies. As a result, developers can use the latest libraries and offer new features without being tied to the system. Snaps also help in treating Linux as single platform instead of looking at each distro as a platform.

Snaps may help bring more mainstream apps to Linux.

Source link

Chromebooks Support Debian Applications » Linux Magazine

Google is finally bringing the ability to install and run traditional Linux apps in Chrome OS. The company announced Project Crostini back in May during the Google I/O event. Initially it was announced for Google Pixel, but support for Linux started landing on supported devices recently.

Chrome Unbox, a site that covers Chrome OS, reported that they have managed to install Debian apps on Chromebook.

If you are running the dev channel of Chrome OS, you can easily enable support for Linux on Chromebooks. All you need to do is go to Settings > About Chrome OS > Detailed build information and change the channel from stable to ‘dev’. It will ask you to powerwash your device, which means deleting all data and re-formatting the machine. Once the device is powerwashed, you would be running the latest dev branch of Chrome OS.

Users running dev channel will notice an option to enable Linux apps under the ‘settings > device’ option. Once you enable Linux, it will download and install the terminal app, which runs Debian with custom packages.

Users can simply run ‘apt-get’ to update Debian on Chromebook and install desired apps. Of course, it’s just the beginning and things need to be ironed out.

Source link

ExTiX 18.7 Is Not Quite an ‘Ultimate Linux System’ | Reviews

By Jack M. Germain

Aug 2, 2018 10:27 AM PT

ExTiX 18.7 Is Not Quite an 'Ultimate Linux System'

The latest release of the
ExTiX Linux distro is a major disappointment.

ExTiX 18.7 has several shortcomings that make it troublesome to use. The flaws easily might be fixed in a patched follow-up release. Still, to a new Linux user, the problems inherent in ExTiX 18.7 give the Linux OS in general a black eye.

New releases of any software platform never come with guarantees. Sometimes, an earlier release works almost flawlessly while its upgrade down the line fails to impress. That was my experience revisiting the ExTix distro.

Despite this down slide, the developers can bounce back. The ExTiX distro offers adopters some features not readily available in other Linux distros.

Last month’s release is built around the LXQt 0.12.0 desktop and is based on Debian 9 Stretch and Ubuntu 18.04 Bionic Beaver. This relatively new desktop environment is the product of merging the LXDE-Qt and the Razor-qt projects.

LXQt is an apt replacement of LXDE, the Lightweight X11 Desktop Environment. The more modern Qt tools bring some freshness to LXDE while shifting the emphasis away from running well on more minimal (as in older) hardware.

Meshing traditional LXDE functionality with the added tweaks from Razor-QT is a big step in a better direction for this lightweight desktop environment. Even this latest ExTiX release, despite its troubles, teases the kind of modern lightweight, modular, fast and user-friendly desktop environment that the distro offers.

Development Trails

Developer Arne Exton created ExTiX and dubbed it “the ultimate Linux system.” It is an offshoot of
Exton Linux/Live Systems, a collection of 16 related Exton Linux distributions hosted by the Swedish Linux Society.

Earlier ExTiX releases offered a variety of desktops, including Budgie, Deepin, KDE and LXQt. So far, only one flavor is available in the 18.7 release.

Both the Exton and ExTiX OSes are linked to download ports on The Exton OS and ExTiX Linux distros all seem related to the common Debian and Ubuntu bases.

Both divisions use a combination of the Calamares installer and Refracta tools. The combination enables users to select their own unique assortment of software and desktop settings for burning to a USB stick or DVD live session.

ExTiX distro Calamares installer

The ExTiX distro uses the Calamares installer to provide simpler options with a more user-friendly interface.

Fatal Attraction

I last
reviewed ExTiX in 2015 after the developer yanked out GNOME and replaced it with the then-brand-new LXQt desktop. I liked the performance of the next generation of the popular LXDE desktop. It was a stable desktop environment usable on production desktop machines, unlike the latest version of ExTiX.

The release notes for ExTiX 18.7 caught my attention. The description of its features suggested an attractive developmental progress that drew me in.

One of the best features promised the ability to run this OS from a hybrid ISO installation to an encrypted USB stick. In addition, you then could get more speed by transferring the system to RAM.

Even better, you could run it from a USB installation in two ways. The built-in persistence would let you save all your system changes on the stick. Or you could run it as a glorified live session with no persistence.

Less Desirable Approach

The RAM installation option provides a lightning fast performance limited only by the amount of onboard memory. Other Linux distros — Puppy Linux for one — pioneered the concept of putting Linux on a stick. This lets you carry all of your applications and files to run on any computer without leaving a trace of your presence behind.

ExTix sort of reinvents that wheel. Unlike other “portable Linux” systems, you can install the ExTiX on the hard drive fully without using so-called frugal installation tricks. When it works, you get a fully functional Linux distro installation.

*When* is the key qualifier in this description. Keep reading to find out the sorted problems that got in my way evaluating this release.

With ExTiX you have more options for DVD and USB installations. You also get a simpler and more flexible user interface with more control over system settings.

ExTix provides two installation options. One is a simple method that transfers the DVD files to the USB stick. The USB connection is faster than the DVD bus. You do not get persistence with this method, however, so you cannot save system settings or new software installations.

For it to work, you either must install Grub or edit the existing Grub configuration file on the host computer into which you will insert the live USB stick. This eliminates the ability to have a pocket distro that you can plug into any computer.

Of course, you can burn a snapshot of your installation to a DVD or USB drive and run it that way on any computer, much like a live session, with or without persistence.

ExTiX System Tools

Two ExTix distro advantages are the improved LXQt desktop over LXDE, and the specialized tools for installing ExTiX to a DVD or USB to run a complete Linux system with or without persistence.

First Impressions

Unlike most live-session DVDs, ExTiX does not have an install launcher on the desktop screen. Instead, you must run Calamares from the System Tools menu. The developers replaced Ubuntu’s installer, Ubiquity.

If your plan is to create a USB or DVD installation, use one of the two Refracta tools, not Calamares, for the installation. You will find them further down the list in the System Tools menu.

Refracta Snapshot lets you create a live installable snapshot of your system. It creates a bootable image that you can burn to CD or DVD. It stores the image in /home/snapshot. The Refracta Installer is the tool for installing an already-created live CD/DVD to your system.

I like that the live session login is automatic. You do not have to supply a password. It is easy to run the live session in system RAM without having to type special commands in an edit window when the DVD initially loads. Just select boot alternative four (Load to RAM). Your system will need at least 2 GB of RAM for this to work.

You can remove the DVD or USB stick once the system loads. This makes it convenient to access your documents while running in Live session without creating persistence. I also like that the developer patched kernel 4.18.0-rc5-extix. This makes it work with Nvidia’s proprietary graphics driver.

The background images are few and boring — that is, unless you like different views and colors of Porsches.

The login screen is weird. It asks for the username in the first window. Then a second window appears without any label. That is where you enter a password.

Failed User Experience

I was very disappointed with the sluggish, broken performance of the ExTiX 18.7 release. It was anything but an ultimate Linux experience. The OS could not get out of its own way sometimes.

I installed this release on four computers. I also installed it to a USB drive and virtual machines on two computers. I ran ExTiX 18.7 booted from live session DVD burned from its ISO made from two separate downloads.

The problems I encountered in one instance occurred in other instances as well. The best speed came from running ExTiX in RAM on a computer with 8 GB.

The difficulties I encountered should happen only in a new alpha or beta release. Among them were sluggish menus, applications that locked up, applications that failed to load, and difficulty connecting to the Internet.

Breakdown Rundown

The problems began with my initial installation efforts. Things cascaded from there. Here is a rundown of my installation woes.

The process took 15 minutes to reach 25 percent transfer to the hard drive. Then the process continued to drag on slowly. The installation ultimately failed, according to a screen report at the end of the installation process, due to an error in updating or reinstalling grub. That error repeated on every installation I attempted.

That left the system unable to boot. On several of the computers dealing with the installation, I had a working dual boot configuration. So ExTiX did not load, and the other partitions also were inaccessible.

A few minutes of tinkering with a Boot-Repair-Disk DVD found and fixed the problem. All seemed well when I once again rebooted the computer. I installed ExTIX on a different computer. This time the same problem occurred with the error message regarding a failed Grub installation.

Again, I used the Repair-Boot-Disk to fix that issue. However, that application did not solve the boot problem. No boot manager was installed. So I tried a second boot repair application to no avail.

Scenario Unfolds

Nothing I tried resolved the missing Grub Manager error until I installed another Linux distro to the ExTiX partition on the hard drive. I recently had completed a review of Peppermint Linux without incident, so I installed that distro to replace ExTiX on the second computer. That process supplied the boot manager, and all was well with accessing the second computer.

At that point, it was clear that a problem seemed to exist with the ExTiX ISO. Or maybe it was an error in the process of creating the ISO from the downloaded package. So I got a fresh download and burned a new ISO to DVD. Nothing changed.

I used the ISO file to create a virtual machine. That process worked as a live session. Then I took the next logical step. I installed ExTiX to a VM rather than run it as a live session from the ISO. That actually worked without major glitches.

Yet some of the other troubles detailed above replicated in the VM. Just as with the other installation attempts, the Network Manager was not connected. Some distros balk at making wireless connections if the hardware is not supported, but the network cable should be an automatic connection.

On a few of the computers, I was able to get the Network Manager to work by re-entering the existing settings. That did not work in other cases. Even when the network connection failed, on some of the computers the wireless connection functioned. Go figure!

ExTiX Network Manager

One of the nagging problems with this ExTiX release is the troubled Network Manager, which either cannot connect to a hard-wired Internet connection or keep the connection stable.

Update Hell

Adding and removing software is handled through the Synaptic Package Manager in ExTiX. Guess what? That application refused to load in every installation except on VMs.

I assumed it had something to do with the error message about the initial installation. So I redid the installation. No dice.

The Synaptic application was in the main menu. The files were where they should have been in the correct system directory. The package manager refused to load except when ExTiX ran in a VM.

In this extreme case, I tried to work around the problem by jockeying .deb files for must-have installations such as Dropbox. That is when I discovered that the GDebi package installer is not included in ExTiX by default. I had to resort to terminal commands for manual installation.

Desktop View

The desktop looks neat and clean. It has the look and feel of the LXDE desktop. The real improvements with the LXQt environment are under its hood. These include better-organized menus, more settings options, and more flexibility with configurations. Out of the box, LXQt is ready to go.

The desktop is devoid of icons. You cannot place launchers there by right-clicking an application in the main menu. You can right-click on the desktop to pop up a context menu with limited options.

A panel bar stretches across the bottom of the screen. It is preconfigured with a workplace switcher applet and two virtual workspaces.

Bottom Line

The ExTiX 18.7 release was a disappointment. Given the maturity and variety of the previous Linux distros maintained by the Exton OS and ExTiX developer, I can only conclude that the problems I encountered were an anomaly. No doubt, a fix is in the works.

I hope so. ExTiX and the LXQt desktop have much to offer. This latest release comes with Firefox instead of Google Chrome as the Web Browser. This makes it possible to watch Netflix movies in Firefox while running Linux.

Among many other programs included are LibreOffice, Thunderbird, GParted, Brasero, SMPlayer, Gimp, Flash and win32 codecs. In addition, Java and all necessary additions are supplied to let you install programs from source.

Want to Suggest a Review?

Is there a Linux software application or distro you’d like to suggest for review? Something you love or would like to get to know?

email your ideas to me, and I’ll consider them for a future Linux Picks and Pans column.

And use the Reader Comments feature below to provide your input!

Jack M. Germain has been an ECT News Network reporter since 2003. His main areas of focus are enterprise IT, Linux and open source technologies. He has written numerous reviews of Linux distros and other open source software.
Email Jack.

Source link

VMware vSphere Storage Types

VMware vSphere supports different types of storage architectures, both internally (in this case the controller is crucial, that must be in the HCL) or externally with shared SAS DAS, SAN FC, SAN iSCSI, SAN FCoE, or NFS NAS (in those case the HCL is fundamental for the external storage, the fabric elements, and the host adapters).

For local storage, with vSphere 6.x it’s possible to use USB disks, not only as boot disks, but also to run VMs. But note that USB datastores are just unsupported by VMware.

Storage types at the VM logical level

There are different types of virtual disks depending on the provisioning method, pre- allocated or dynamic. The type of virtual disks are mainly the same since vSphere 4.0:

  • An eager zeroed thick disk has all space allocated and wiped clean of any previous content on the physical media at creation time. Such disks may take a long time during creation compared to other disk formats. The entire disk space is reserved and unavailable for use by other VMs.
  • Thick or lazy zeroed thick VMDK: A thick disk has all space allocated at creation time. This space may contain stale data on the physical media. Before writing to a new block, a zero has to be written, increasing the input/output operation per second (IOPS) on new blocks compared to eager disks. The entire disk space is reserved and unavailable for use by other VMs.
  • Thin VMDK: Space required for the thin-provisioned virtual disk is allocated and zeroed on demand as space is used. Unused space is available for use by other VMs.

You can choose the disk provisioning type during virtual disk creation, but you can change the type using a cold VM migration across two datastores, or using Storage vMotion (if you have at least ESXi Standard edition). Note that you can also change the type of each individual disk, by choosing Configure per disk on the new HTML5 client shown as follows:

(Click on image for larger view)

There are also Raw Device Mapping (RDM) disks where a disk at ESXi level is mapped 1:1 to a VM (like a Passthrough mode), with two different types of compatibility (virtual or physical mode). Except for building guest clusters (clusters across VMs on different hosts), there is no need to use these types of disk.

There is no significant difference in performance for sequential I/O between the different types of virtual disks. For random I/O, thin VMDKs have the worst performance and higher latency (for lazy thick, it depends if you have to write a new block).

Storage types at the VM physical level

To access a block device, such as virtual disks VMDK, virtual CD/DVD-ROM, or other SCSI devices, each VM uses storage controllers; at least one is added by default when you create a VM.

There are different types of controller available for a VM running on ESXi which are described as follows:

  • BusLogic: This is one of the first emulated SCSI virtual controllers available in VMware ESX. Now it’s a legacy controller used mainly for legacy operating systems. It does not support VMDK larger than 2 TB.
  • LSI Logic Parallel: This was formally known as LSI Logic and was the other SCSI virtual controller available originally in VMware ESX, used for operating systems such as Windows Server 2003.
  • LSI Logic SAS: This was introduced in vSphere 4.0, and is the evolution of the parallel driver, working as a SAS virtual controller and used in Windows Server 2008 or newer.
  • VMware Paravirtual (or PVSCSI): This was introduced in vSphere 4.0, is an SCSI virtual controller designed to support very high throughput with minimal processing cost, working not in emulation mode, but in paravirtual mode (it requires the VMware Tools to be recognized).

Others virtual controllers are also possible in a VM, such as AHCI SATA (introduced in vSphere 5.5), IDE, and also USB controllers, but usually for specific cases (for example SATA or IDE are usually used for virtual DVD drives).

Note: When you create a VM, the default controller is optimized for good performance and compatibility. The controller type depends on the guest operating system (usually its driver is included in the operating system), the device type, and sometimes, the VMs compatibility. But sometimes you can choose a different controller to improve the performance, like the PVSCI (useful for VMFK with high load) or a new type available in vSphere 6.5.

With ESXi 6.5 and VM virtual hardware version 13, you can now also use a virtual NVMe. Virtual NVMe devices have reduced guest I/O processing overheads (over 50% compared to AHCI SATA SCSI device), which allows more VMs per host or more transactions per minute. Each virtual machine supports 4 NVMe controllers and up to 15 devices per controller.

Virtual NVMe controllers are supported on vSphere 6.5 only on the following guest operating systems:

  • Windows 7 and 2008 R2 (hotfix required, refer to
  • Windows 8.1, 2012 R2, 10, 2016
  • RHEL, CentOS, NeoKylin 6.5, and later Oracle Linux 6.5 and later
  • Ubuntu 13.10 and later
  • SLE 11 SP4 and later
  • Solaris 11.3 and later
  • FreeBSD 10.1 and later
  • Mac OS X 10.10.3 and later
  • Debian 8.0 and later

You can add a new NVMEe virtual controller using the vSphere Web Client (from the HTML5 web client is not yet possible) as shown in the following steps:

  1. Right-click on the virtual machine in the inventory and select Edit Settings option
  2. Click the Virtual Hardware tab, and select NVMe Controller from the New device drop-down menu
  3. Click on Add
  4. The controller appears in the Virtual Hardware devices list
  5. Click OK

(Click on image for larger view)

For more information on NVMe, see also KB 2147714—Using Virtual NVMe with ESXi 6.5 and virtual machine Hardware Version 13 (

For more information on PVSCI, see also KB 1010398—Configuring disks to use VMware Paravirtual SCSI (PVSCSI) adapters (

Storage types at the ESXi logical level

At the high level, VMware vSphere will access each storage using datastores—a logical paradigm to abstract all storage types, like a common operating system uses letters or mount points to access a filesystem.

VMware vSphere 6.x has the following four main types of datastore:

  • VMware FileSystem (VMFS) datastores: All block-based storage must be first formatted with VMFS to transform a block service to a file and folder oriented services
  • Network FileSystem (NFS) datastores: This is for NAS storage
  • VVol: This is introduced in vSphere 6.0 and is a new paradigm to access SAN and NAS storage in a common way and by better integrating and consuming storage array capabilities
  • vSAN datastore: If you are using vSAN solution, all your local storage devices could be polled together in a single shared vSAN datastore

New datastores could be provisioned from the new HTML5 client, starting from a data centre, a cluster, or a host; just right-click on the object, choose storage, and then new datastore:

(Click on image for larger view)

For local disks, if you have configured the right RAID level from the controller (remember that ESXi does not provide software RAID features), you can just format the logical disks with a VMFS datastore.

But before external storage, before adding a new datastore, you must first configure the ESXi host, the fabric, (if present) and the storage itself. This depends on the storage type and vendor and will be discussed later. You cannot directly add a vSAN datastore; the vSAN configuration is quite different, but the final result will be a vSAN datastore with its own format.

Of course, on the same host you can have multiple datastores, also with different types:

(Click on image for larger view)

At the datastore level, there isn’t any difference between DAS or SAN, they are just block- based storage and become VMFS datastores. The functional difference is that a SAN disk could be shared across multiple hosts, not local DAS disks (but there are also shared SAS storages that are formally classified as DAS storage).

Storage types at the ESXi physical level

Excluding vSAN, which has a specific configuration, at the physical level we can have three different main types of storage:

  • Block-based storage acceded by a hardware adapter: This includes DAS storage or a SAN FC storage.
  • Block-based storage acceded by a software adapter: This is like the SAN iSCSI storage when the software initiator is used. In this case, you need first to properly configure the network connectivity. After that, it becomes very similar to the first case.
  • NFS storage: This is where you have to configure first the IP network connectivity to your storage and then connect the NFS datastore.

For the physical storage adapters, VMware ESXi supports several types of protocols and technologies (refer to the hardware compatibility list to check the supported level):

  • Fibre Channel Host Bus Adapter (FC HBA): This is the common and historical way to implement an FC-based storage, but using a dedicated full fabric.
  • iSCSI HBA: These are specialized PCIe cards that implement completely in hardware the entire iSCSI stack, reducing the load of the host CPU.
  • CNA adapters for FCoE or iSCSI: These are mostly 10 Gbps (or greater) Ethernet adapters providing hardware (or hardware assisted) FCoE or iSCSI functionality on converged (or also dedicated) networks.
  • RDMA over Converged Ethernet (RoCE): This is a network protocol that allows remote direct memory access (RDMA) over an Ethernet network. Starting with vSphere 6.5, RoCE certified adapters could be used for converged networks. InfiniBand HCA: Mellanox Technologies InfiniBand HCA device drivers are available directly from Mellanox Technologies. Mostly used for the network part instead of the storage part, they could be interesting in converged networks, and also in vSAN implementation.

This tutorial is an excerpt from “Mastering VMware vSphere 6.5” by Andrea Mauro, Paolo Valsecchi & Karel Novak and published by Packt. Get the ebook for just $9 until Aug. 31.

Source link