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NewsVac: News from around the Web
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Scale your file system with Parallel NFS
1 year ago
The Network File System (NFS) is inadequate for the demanding input- and output-intensive applications commonly found in high-performance computing—or, at least it was. The newest revision of the NFS standard includes Parallel NFS (pNFS), a parallelized implementation of file sharing that multiplies transfer rates by orders of magnitude. -
Cisco Unleashes Big Routers For Video
1 year ago
Cisco claims new ASR 9000 offers the best platform ever for video and other service delivery with Terabits of capacity. -
Implement lower time granularity for retransmission of TCP
1 year, 1 month ago
Reduce the overhead of per-tick processing with a timer wheel algorithm that implements the retransmission timer. In this article, learn how to get lower granularity with your retransmission timer by using the AIX TCP fast timer, and discover other advantages of lower timer granularity. -
Networks: The Crux of Tomorrow's Datacenter
1 year, 3 months ago
Perhaps Scott McNealy was right when he said "the network is the computer" all those years ago, and the next generation of datacenters will bear that out. -
Researchers could face legal risks for network snooping
1 year, 4 months ago
A group of researchers from the University of Colorado and University of Washington could face both civil and criminal penalties for a research project in which they snooped on users of the Tor anonymous proxy network. Should federal prosecutors take interest in the project, the researchers could also face up to 5 years in jail for violating the Wiretap Act. -
Meet Squid
1 year, 4 months ago
Squid is a caching proxy server that can provide enhanced performance for HTTP and FTP. Squid will cache commonly accessed sites so that it can improve performance by 10-20% for Internet connections. -
Netgear's open wireless-G router for open source hackers
1 year, 4 months ago
"NETGEAR has announced a wireless router specifically targeted at the Linux community. The WGR614L is based on a MIPS CPU with 16M of RAM an 4M of flash, along with 802.11g and 10/100 ethernet connectivity. It currently runs Tomato and DD-WRT firmware and will soon add support for OpenWRT." -
From Live Mesh to the Open Mesh
1 year, 6 months ago
Marc Canter has written a series of blog posts outlining the issues, constructs, technologies, and standards required to build out an"open mesh." -
Cisco:networking is hot again
1 year, 6 months ago
NAC, Trustsec, PCI, Linux and more are all on the table as Cisco VP outlines the network giant's strategy moving forward. -
Why we should care about the spectrum debate
1 year, 8 months ago
The debate of who should manage the wireless spectrum and whether it should be open is key to the future of mobile and personal computing, experts say. -
Muni Wi-Fi's second chance
1 year, 8 months ago
Wi-Fi networks can work with a little tweaking, a new study finds. -
IPv6 and IPv4 - big trouble coming, and soon
1 year, 9 months ago
You'll know that most of the Internet runs on IP version 4, the first cut of the Internet Protocol to see widespread use. It was standardised in 1981; for the past twenty five years or so, it's underpinned the beyond-massive expansion of the Internet. -
AT&T to crush copyrighted network packets
1 year, 10 months ago
"AT&T says it's time to start filtering copyrighted content at the network level. During a panel discussion at the International Consumer Electronics Show (CES), The New York Times reports, the communications giant joined Microsoft and NBC Universal in arguing that internet service providers - like AT&T itself - should be sniffing your networks packets and blocking anything that copyright holders don't traveling over the wire." -
IPv6 Set for Root Adoption?
1 year, 10 months ago
IPv6 adoption has a key adoption deadline looming this year, but is still facing plenty of barriers to adoption. Key among them is this: IPv6 address information is not included in most of the root DNS servers that power the Internet. This makes IPv6 to IPv6 connections a difficult proposition. -
Book review: Linux Networking Cookbook
1 year, 11 months ago
"Linux networking cookbook is a book for both a seasoned and new Linux network administrator. It includes valuable time saving recipes, tools and related resources. The book is written in clear and concise style with tons of examples and working code .... " - More News
Linux.com : Networking
Keeping an eye on your network with PasTmon
The PasTmon passive traffic monitor keeps an eye on your network, recording which clients are interacting with which services, when and how long things took. You can then use the application's PHP Web interface to investigate these figures to see if any host is connecting to Web services that it shouldn't, or is contacting services suspiciously more frequently than you would expect for normal operation, or when response times become excessively long.
Keeping tabs on your network traffic
One of the first things I do upon installing a Linux distribution is put the Network Monitor applet on my GNOME panel. Watching the blue lights twinkle on and off makes me aware of network traffic. But if you want more details about what's happening on your network, such as which application is hogging bandwidth or what each network interface is up to, you can turn to specialty tools like NetHogs and IPTraf. While NetHogs is a unique tool altogether, IPTraf can be used on a server as well as by a home user.
Speed up your Internet access using Squid's refresh patterns
Bandwidth limitation is still a problem for a lot of people who connect to the Internet. You can improve your available bandwidth by installing Squid caching proxy server on your network with configuration parameters that will increase your byte hit rate, giving you about 30-60% more bandwidth.
Access remote network services with SSH tools
You probably rely on the services on your own private network -- wikis, mail servers, Web sites, and other applications you've installed. What happens when you have to leave the friendly confines of your network? With minimum exposure and few simple tools, you can get all of the comforts of home anywhere you can find an Internet connection.
Parallel SSH execution and a single shell to control them all
Many people use SSH to log in to remote machines, copy files around, and perform general system administration. If you want to increase your productivity with SSH, you can try a tool that lets you run commands on more than one remote machine at the same time. Parallel ssh, Cluster SSH, and ClusterIt let you specify commands in a single terminal window and send them to a collection of remote machines where they can be executed.
Monitor your network with GroundWork Monitor Community Edition
A reliable network monitoring and management solution must accurately detect network devices such as routers, servers, and client workstations. It must be able to display a map of the whole network, monitor the health and performance of each device, and have a way to notify someone of a problem by email, text message, or other form of communication. It should be able to fix a problem by restarting services or running specific programs. It should generate detailed reports that you can analyze easily to help prevent future incidents. Finally, a decent monitoring system must be easy to use, deploy, and customize according to your monitoring needs. Let's use these standards to see if GroundWork Monitor Community Edition is up to the task.
Enhance your DNS and DHCP services with dnsmasq
When a network is small and most of its users interact chiefly with services on the Internet at large, it's easy to get by simply by assigning numeric Internet Protocol addresses to your nodes rather than names. As the network grows, however, and as internal services (wikis, mail servers, media servers, and more) come online, recalling numeric addresses becomes unwieldy. One solution is to implement Domain Name Server (DNS) and Dynamic Host Configuration Protocol (DHCP) with dnsmasq, and thereby cache external DNS addresses for performance reasons, dynamically assign IP addresses to all of the members of your network, and manage everything from one location. This article shows you how.
Protect your network with pfSense firewall/router
pfSense is a free, powerful firewall and routing application that allows you to expand your network without compromising its security. Started in 2004 as a child project of m0n0wall -- a security project that focuses on embedded systems -- pfSense has had more than 1 million downloads and is used to protect networks of all sizes, from home offices to large enterprises. pfSense has an active development community, and more features are being added in each release to further improve its flexibility, scalability, and, of course, security.
Simplify system security with the Uncomplicated Firewall
The Uncomplicated Firewall (UFW) is a new tool from Ubuntu whose goal is to make configuration of the built-in Linux packet filter less complicated and more secure for novice users.
Push and pull network filesystems with ccgfs
The CC Network Filesystem (ccgfs) lets you mount filesystems over the network using either the push or pull model for connections. Most network filesystems use the pull model, where the client mounts a network share and all connections originate from the client. Using the push model for network shares means that all connections originate from the server. The push model has advantages when you want a machine on your network demilitarized zone (DMZ) to access a file server through a firewall.
Devil-Linux distro bundles router/firewall and server in one live CD
Devil-Linux might sound hellish for a Linux distribution, but this live CD offers many blessings for your server needs. Originally developed as a router/firewall distribution, Devil-Linux has expanded its functionality to include nearly every service that a server might offer. It can function as an LDAP server, a VPN server, an email or file server, and more.
Umit, the graphical network scanner
Umit is a user-friendly graphical interface to Nmap that lets you perform network port scanning. The utility's most useful features are its stored scan profiles and the ability to search and compare saved network scans. A profile lets you configure how a network scan is performed, change the source information for the scan, and explicitly nominate hosts to include or exclude from the scan, as well as various more advanced options.
Implement load-balancing, port forwarding, and rate-limiting with shd-tcp-tools
shd-tcp-tools provides a collection of tools for port forwarding, load balancing, and rate-limiting TCP connections. They can be useful if you want to offer SSH services but also limit how much of your bandwidth each user can consume, so that a single long-running SCP operation cannot starve the link from your server to the Internet.
Turn your machine into enterprise storage with Openfiler
In my job as a systems engineer, I have handled various storage implementations for our enterprise clients. These may be in the form of direct-attached storage (DAS), network-attached storage (NAS), storage area network (SAN), or Internet Small Computer System Interface (iSCSI) systems. In these implementations, clients generally use proprietary storage products from vendors such as EMC, Dell, Hewlett-Packard, and EqualLogic. Many of these devices work just like ordinary servers with multiple hard disks and an operating system. Some use Unix and Linux as base operating systems, so I began to explore the possibility of using that kind of operating system on ordinary servers to turn them into storage boxes. I found Openfiler, which supports most storage protocols and can save you $5,000 or more by providing enterprise-level storage absolutely free for any box that meets the minimum requirements.
Gerald Carter of Likewise talks about LDAP for Linux (video)
Some GNU/Linux desktop deployments require secure authentication from a Windows Active Directory server. Gerald Carter, a long-time member of the Samba team and an enthusiastic free software developer, now works for Likewise. You can learn from this discussion if you are considering becoming a software developer, are looking for a good business model for your free software-based company, or are looking to manage your network more securely.
A hands-on look at Vyatta Community Edition 4 networking software
Vyatta offers hardware and open source software for enterprise-level network infrastructure. Vyatta can turn any 32-bit x86 machine with at least one network interface into a network appliance that handles routing, firewall, and VPN tasks. The company released Vyatta Community Edition 4 in April, with improved scalability and feature enhancements. Large enterprises now have a low-cost alternative to proprietary hardware like the Cisco 7200.
Benchmarking network performance with Network Pipemeter, LMbench, and nuttcp
Network latency and bandwidth are the two metrics most likely to be of interest when you benchmark a network. Even though most service and product advertising focuses on bandwidth, at times the latency can be a more important metric. Here's a look at three projects that include tools to test your network performance: nepim "network pipemeter," LMbench, and nuttcp.
ssh-xfer: Quickly grabbing files over an existing SSH connection
The Secure Shell (SSH) and Secure Copy (SCP) make remotely performing system administration and copying files across secure links a painless operation. SSH and SCP use the same SSH protocol to protect network communications, but they rely on users knowing if they want a shell or to copy a file beforehand. You cannot easily use an existing SSH shell connection to a remote machine and just grab one or two files; if you want the files, you'll have to make another SSH connection for the file copy using SCP -- unless you have ssh-xfer.
autonom.us aims to be think-tank on network service software licensing issues
Network services are one of the fastest growing areas in modern software. However, while network services have much of the convenience of free software, only a minority are available under a free license. In fact, it was only last November that the Free Software Foundation (FSF) released the GNU Affero General Public License for network services. Under these conditions, last week's announcement of the formation of autonom.us, a new activist group "to focus on issues of software freedom in network services," seems overdue. The group's immediate plans are still evolving, but currently, its main goal -- so far as it has one yet -- seems to be as a policy discussion and advocacy group.
The power of cross-platform synchronization
These days there are plenty of ways to back up your computer files. The options are easy when you're dealing with one computer -- just back up your files to an external hard drive and forget about it -- but when several machines are involved, each with a different operating system, things can get complicated. If you frequently work on more than one computer, having access to your synchronized files no matter where you are can also be useful. PowerFolder, a backup and file synchronizing service, helps you cover all your bases, no matter what platform or how many computers you're using.
