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Canonical and Ubuntu Helped Munich Save Millions of Dollars by Ditching Microsoft Products
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![](http://i1-news.softpedia-static.com/images/news2/Canonical-and-Ubuntu-Helped-Munich-Save-Millions-of-Dollars-By-Ditching-Microsoft-Products-450571-2.jpg)
**The City of Munich has become one of the most prominent examples of a city administration that switched from Microsoft products to open source, and it looks like Canonical and Ubuntu were an instrumental part of that change.**
The City of Munich managed to shake off the Microsoft dependency, but it took a lot of work and it wasn't cheap. The benefits of moving from Microsoft products to open source might look expensive, but the costs are significantly lower than an upgrade, and it will prove to be a lot cheaper in the future.
Moving from a proprietary solution to an open source one is not all that simple when you have a city the size of Munich. It has 22 organizational units and each of those units has its own IT department, not to mention different versions of the applications.
The local authorities couldn't just adopt a Linux distribution on the fly. The first try was made with Debian back in 2006, but that particular OS didn't have a predictable release schedule. This is how the new LiMux was born, an operating system based on Ubuntu.
“The LiMux/open source project was a long and iterative one, but after a few years of running such a large Linux base, we realized Ubuntu was the platform that could satisfy our requirements best. By combining the low costs and freedom of open source software with ongoing support for the hardware and applications we need, it was one of the critical elements to the success of this project. Most important was the backing of our politicians throughout the project,” [said][1] Peter Hofmann, project manager for the City of Munich.
This tremendous project helped Munich save €10 million ($13.6 million) by 2013, but that is if we take into consideration only the upgrade costs. That sum might be a lot bigger if we could quantify the official support for the software and other hidden costs.
Right now, in Munich, there are 14,000 PCs that are running LiMux and that number is still increasing. It's very likely that other German cities will do the same in the future, especially the ones neighboring Munich.
It took the authorities of Munich 13 years to finish the transition, but in the end they managed to save a lot of money and prove that Linux is actually a very good and free solution for the IT infrastructure of an entire city.
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via: http://news.softpedia.com/news/Canonical-and-Ubuntu-Helped-Munich-Save-Millions-of-Dollars-By-Ditching-Microsoft-Products-450571.shtml
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[1]:https://insights.ubuntu.com/2014/07/07/ubuntu-and-open-source-help-the-city-of-munich-save-millions/

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IPFire 2.13 Core 77 Linux Firewall Distro Brings Major OpenVPN Improvements
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![](http://i1-news.softpedia-static.com/images/news2/IPFire-2-13-Core-77-Linux-Firewall-Distro-Brings-Major-OpenVPN-Improvements-450605-2.jpg)
**Michael Tremer, a developer for the ipfire.org team, has announced that IPFire 2.13 Core 79, a new stable build of the popular Linux-based firewall distribution, is now out with some exciting new features.**
IPFire is a modular Linux distribution, which means that it can be deployed as a firewall, a proxy server, or a VPN gateway. The main concern of the developers is security and every step has been taken in order to ensure that users can feel really safe when using this operation system.
The developers are saying in the official [announcement][1] that the “Core Update 79 is finally arriving with many bug fixes and enhancements. Among the big changes with this update are lots feature enhancements that massively increase the security level of OpenVPN connections, some enhancements of the web user interface and a lot more awesome stuff under the hood.”
The IPFire devs had another huge release a few months ago and it looks like they have made another one, this time focusing on the improvement of the OpenVPN features and a few other aspects.
“The certificate authority that can be created on the OpenVPN page now uses much better hashes to protect the integrity of itself. The CA root certificate uses a SHA512 hash and a RSA key with length of 4096 bit. All new created host certificates use a RSA key with 2048 bit length and a SHA256 hash. Additionally, a set of Diffie-Hellman parameters can be generated for better protection of the session keys. The length of the pregenerated DH parameters can be chosen in the web interface,” also noted the devs.
According to the changelog, the cipher that is used for each net-to-net connection can now be changed, the hash function is now configurable with a few options like SHA2 (512, 384, and 256-bit), Whirpool (512 bit), and SHA1 (160 bit), and the tls-auth option can be enabled, which uses a HMAC function.
The Linux kernel used by the distribution has also been updated in this release and the OS now packs the 3.10.44 version. This should bring support for new hardware, a number of security fixes, and more stability.
Also, snort (the Intrusion Detection System) has been updated to version 2.9.6.1, the new firewall GUI now supports blocking access to the GREEN firewall interface, the PIE packet scheduler has been added, and the default size of the root partition has been increased.
The developers recommend all users of IPFire to upgrade their distributions. More details can be found on the official website.
Download IPFire 2.13 Core 79:
- [IPFire 2.15 Core 79][1] (ISO)[iso] [126 MB]
- [IPFire 3.0 Alpha 1][2] (ISO)[iso] [76 MB]
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via: http://news.softpedia.com/news/IPFire-2-13-Core-77-Linux-Firewall-Distro-Brings-Major-OpenVPN-Improvements-450605.shtml
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[1]:http://www.ipfire.org/news/ipfire-2-15-core-update-79-released
[2]:http://downloads.ipfire.org/releases/ipfire-2.x/2.15-core79/ipfire-2.15.i586-full-core79.iso
[3]:http://www.rowie.at/ipfire/iso/ipfire-3.0-alpha1.i686.iso

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LFTP 4.5.3 File Transfer Software Is for People Who Love the Terminal
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![](http://i1-news.softpedia-static.com/images/news2/LFTP-4-5-3-File-Transfer-Software-Is-for-People-Who-Love-the-Terminal-450596-2.jpg)
**LFTP 4.5.3, a sophisticated file transfer program with a command-line interface that supports FTP, HTTP, FISH, SFTP, HTTPS, and FTPS protocols, has been released and is ready for download.**
Every operation made with LFTP is reliable, which means that, if any non-fatal error occurs, the operation is retried automatically. The software supports numerous protocols, but it can also handle a few other tasks, such as BitTorrent downloads, SRV DNS records, job queuing, bookmarks, aliases, and many more.
“lftp has shell-like command syntax allowing you to launch several commands in parallel in background (&). It is also possible to group commands within () and execute them in background. All background jobs are executed in the same single process. You can bring a foreground job to background with ^Z (c-z) and back with command wait (or fg which is alias to wait),” reads the official website.
According to the changelog, a new setting ftp:site has been added, the http body is not uncompressed when the Contrent-Type is compressed, the source address of DHT replies is now checked, and the disconnected torrent peers are now discarded after only a timeout.
A complete list of changes and improvements can be found in the official [announcement][1].
Download LFTP 4.5.3:
- [LFTP 4.5.3 tar.xz][2][sources] [1.40 MB]
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via: http://news.softpedia.com/news/LFTP-4-5-3-File-Transfer-Software-Is-for-People-Who-Love-the-Terminal-450596.shtml
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[1]:http://lftp.yar.ru/news.html
[2]:http://lftp.yar.ru/ftp/lftp-4.4.15.tar.xz

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Linux slabtop command - Display Kernel Slab Cache Information
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The Linux kernel needs to allocate memory for temporary objects such as task or device structures and inodes. The caching memory allocator manages caches of these types of objects. The modern Linux kernel implements this caching memory allocator to hold the caches called the slabs. Different types of slab caches are maintained by the slab allocator. This article concentrates on the slabtop command which shows real-time kernel slab cache information.
### 1. Command Usage: ###
The command is simple to use. Default execution does not mandate any arguments to the command. But it does require root privileges to access the kernel slab information. Executing the command as normal user gives following error:
![Run slabtop as non-privileged user](http://linoxide.com/wp-content/uploads/2014/07/001.slabtop_normal_user.png)
You can run it by prepending “sudo” with slabtop. The default output looks like:
![Slabtop default output](http://linoxide.com/wp-content/uploads/2014/07/002.slabtop_output.png)
To quit from slabtop, just hit q like you do for top command.
### 2. Slabtop options: ###
#### 2.1 Display Interval: ####
By default slabtop refreshes every 3 seconds. But if you want, you can provide the refreshing interval in seconds with -d or --delay=N option:
![Custom delay interval 01](http://linoxide.com/wp-content/uploads/2014/07/003.slabtop_delay01.png)
![Custom delay interval 02](http://linoxide.com/wp-content/uploads/2014/07/004.slabtop_delay02.png)
#### 2.2 Sort criteria: ####
There are many fields in slabtop output. The -s or --sort=S option sorts the output according to the mentioned sort criteria. This option will be discussed in detail in the next section.
#### 2.3 Output once: ####
The -o or --once option does not refresh the output, instead it just throws the output once on STDOUT and exits.
![Output once and exit](http://linoxide.com/wp-content/uploads/2014/07/005.slabtop_output_once.png)
#### 2.4 Version info: ####
The -V or --version displays the version of the command and exits.
![Slabtop version](http://linoxide.com/wp-content/uploads/2014/07/006.slabtop_version.png)
#### 2.5 Help: ####
The common option, -h or --help displays usage of the command.
![Slabtop help options](http://linoxide.com/wp-content/uploads/2014/07/007.slabtop_help.png)
### 3. Sort Criteria: ###
The sort criteria determines which slab caches are displayed on top. Following are the sort criteria for slabtop:
#### 3.1 ACTIVE: ####
Caches can be sorted by number of active objects with “a”.
![Sort by Active 01](http://linoxide.com/wp-content/uploads/2014/07/008.slabtop_sort_active01.png)
![Sort by Active 02](http://linoxide.com/wp-content/uploads/2014/07/009.slabtop_sort_active02.png)
#### 3.2 OBJ/SLAB: ####
The Objects per Slab can be selected with “b”.
![Sort by objects per slab 01](http://linoxide.com/wp-content/uploads/2014/07/010.slabtop_sort_objslab01.png)
![Sort by objects per slab 02](http://linoxide.com/wp-content/uploads/2014/07/011.slabtop_sort_objslab02.png)
#### 3.3 CACHE SIZE: ####
For selecting cache size, you need to provide “c”.
![Sort by cache size 01](http://linoxide.com/wp-content/uploads/2014/07/012.slabtop_sort_cache_size01.png)
![Sort by cache size 02](http://linoxide.com/wp-content/uploads/2014/07/013.slabtop_sort_cache_size02.png)
#### 3.4 SLABS: ####
The number of slabs. Select it with “l”
![Sort by number of slabs 01](http://linoxide.com/wp-content/uploads/2014/07/014.slabtop_sort_slabs01.png)
![Sort by number of slabs 02](http://linoxide.com/wp-content/uploads/2014/07/015.slabtop_sort_slabs02.png)
#### 3.5 Active Slabs: ####
The number of Active Slabs. (Note that this is different from number of Active Objects described above.) Use “v” to sort according to this criteria.
![Sort by Active Slabs 01](http://linoxide.com/wp-content/uploads/2014/07/016.slabtop_sort_active_slabs01.png)
![Sort by Active Slabs 02](http://linoxide.com/wp-content/uploads/2014/07/017.slabtop_sort_active_slabs02.png)
#### 3.6 NAME: ####
Name of cache. Corresponding character is “n”
![Sort by cache name 01](http://linoxide.com/wp-content/uploads/2014/07/018.slabtop_sort_cache_name01.png)
![Sort by cache name 02](http://linoxide.com/wp-content/uploads/2014/07/019.slabtop_sort_cache_name02.png)
#### 3.7 OBJS: ####
To sort by number of objects, use “o”
![Sort by number of objects 01](http://linoxide.com/wp-content/uploads/2014/07/020.slabtop_sort_objectnunber01.png)
![Sort by number of objects 02](http://linoxide.com/wp-content/uploads/2014/07/021.slabtop_sort_objectnunber02.png)
#### 3.8 Pages Per Slab: ####
“p” will sort by pages per slab
![Sort by pages per slab 01](http://linoxide.com/wp-content/uploads/2014/07/022.slabtop_sort_pagesperslab01.png)
![Sort by pages per slab 02](http://linoxide.com/wp-content/uploads/2014/07/023.slabtop_sort_pagesperslab02.png)
#### 3.9 OBJ SIZE: ####
The object size is sorted by “s”
![Sort by object size 01](http://linoxide.com/wp-content/uploads/2014/07/024.slabtop_sort_object_size01.png)
![Sort by object size 02](http://linoxide.com/wp-content/uploads/2014/07/025.slabtop_sort_object_size02.png)
#### 3.10 USE: ####
“u” sorts by the cache utilization.
![Sort by cache utilization 01](http://linoxide.com/wp-content/uploads/2014/07/026.slabtop_sort_cache_utilization01.png)
![Sort by cache utilization 02](http://linoxide.com/wp-content/uploads/2014/07/027.slabtop_sort_cache_utilization02.png)
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via: http://linoxide.com/linux-command/kernel-slab-cache-information/
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