- wlug - list.wlug.org.nz

Network latency simulation
by Glenn Ramsey 28 Nov '07

28 Nov '07

Hi, In order to test some software I am developing I need to introduce a network delay between a machine and the rest of my LAN. After a bit of web searching I discovered that this is supposed to be simple to do, you just set up Linux as a transparent bridge and use the iproute tools to simulate network behaviour. However I can't get it to work how I want. I have an old AMD K6/500 box with 2 10bT ethernet cards running Xubuntu 7.10. One card is connected to my office LAN switch and the other to a hub, like this: MachineA---switch---eth0/bridge/eth1---hub---MachineB I have installed bridge-utils and iproute and I have configured the bridge machine according to the bridge-utils documentation by removing the eth0 and eth1 entries and adding a br0 to /etc/network/interfaces : auto br0 iface br0 inet static address 192.168.1.251 network 192.168.1.0 netmask 255.255.255.0 broadcast 192.168.1.255 gateway 192.168.1.1 bridge_ports eth0 eth1 This works fine and MachineB can get an address via DHCP and see the rest of the network. Now I need to add a delay so that all traffic between MachineB and the rest of the network has some latency. In order to add a delay, according to [1] I just need to do this: $ tc qdisc add dev DEV root netem delay 100ms I have done this for various combinations of eth0, eth1 and br0 but it only seems to delay traffic to and from the bridge itself, not traffic being relayed through the bridge. Does anyone know how to set this up to delay traffic going through the bridge? Glenn [1] http://www.linux-foundation.org/en/Net:Netem#Emulating_wide_area_network_de… -- Glenn Ramsey <glenn(a)componic.co.nz> 07 8627077 http://www.componic.co.nz

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RandR
by Ian McDonald 28 Nov '07

28 Nov '07

Given graphics was focus of last meeting this might be of interest: http://www.phoronix.com/scan.php?page=article&item=927&num=1 Talks about RandR 1.2 and how to use it. -- Web1: http://wand.net.nz/~iam4/ Web2: http://www.jandi.co.nz Blog: http://iansblog.jandi.co.nz

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Fwd: "Open Source DataTurbine Initiative" Biology lunchtime seminar tomorrow (fwd)
by Ian McDonald 25 Nov '07

25 Nov '07

---------- Forwarded message ---------- From: Tony McGregor <tonym(a)waikato.ac.nz> Date: Nov 26, 2007 10:22 AM Subject: "Open Source DataTurbine Initiative" Biology lunchtime seminar tomorrow (fwd) To: cs-staff(a)cs.waikato.ac.nz > Open Source DataTurbine Initiative > > Tony Fountain, Paul Hubbard, Sameer Tilak, Ilya Zaslavsky > University of California, San Diego > > The vision of large-scale sensor-based Observing Systems, to address > the U.S. National Research Council's "Grand Challenges" for > environmental science, relies on robust cyberinfrastructure. Streaming > data middleware is an essential component of this cyberinfrastructure, > providing the foundation for reliable data acquisition and instrument > management services. The environmental science and engineering > communities are currently engaged in the early planning and > development phases of the next generation of large-scale sensor-based > observing systems. The Open Source DataTurbine Initiative is a new > NSF-funded project to empower these communities with Streaming Data > Middleware. > > Large-scale sensor-based observing systems face a number of > significant challenges in design and operations, including > heterogeneity of instrumentation and complexity of data stream > processing. These systems incorporate instruments from across the > spectrum of complexity, from temperature sensors to acoustic Doppler > current profilers, to streaming video cameras. They typically require > integration of instruments from various vendors and R&D labs. > Requirements on the cyberinfrastructure include scalable and secure > support for real-time data acquisition, instrument and data stream > management, and analysis and visualization. To address these > cyberinfrastructure challenges in a principled manner, we launched the > Open Source DataTurbine Initiative. > > DataTurbine is a robust open-source streaming data middleware system > that satisfies the core requirements for sensor-based environmental > observing systems. It is relatively mature and has been tested in a > variety of real-world streaming data applications. It facilitates the > development of complex distributed streaming data applications, > including real-time virtual observatories and telepresence > collaboratories. The Open Source DataTurbine Initiative combines > commercial-quality software support with an active and engaged user > and developer community. In this talk we share our vision and invite > domain scientists and developers to join the Open Source DataTurbine > Initiative. We also discuss our experiences and results from > real-world deployments of DataTurbine. Further details about the Open > Source DataTurbine Initiative can be found at: > http://www.dataturbine.org > > > When: Tues 27th Nov 12:00noon > Where: Room A.G.30 > > <<37 sem 271107 Fountain.doc>> > Vicki Smith > Administrative Assistant > Biological Sciences > The University of Waikato > Private Bag 3105 > Hamilton > > Ph 838 4148 > Fax 838 4324 > > -- Web1: http://wand.net.nz/~iam4/ Web2: http://www.jandi.co.nz Blog: http://iansblog.jandi.co.nz

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Fwd: "Open Source DataTurbine Initiative" Biology lunchtime seminar tomorrow (fwd)
by Ian McDonald 25 Nov '07

25 Nov '07

---------- Forwarded message ---------- From: Tony McGregor <tonym(a)waikato.ac.nz> Date: Nov 26, 2007 10:22 AM Subject: "Open Source DataTurbine Initiative" Biology lunchtime seminar tomorrow (fwd) To: cs-staff(a)cs.waikato.ac.nz > Open Source DataTurbine Initiative > > Tony Fountain, Paul Hubbard, Sameer Tilak, Ilya Zaslavsky > University of California, San Diego > > The vision of large-scale sensor-based Observing Systems, to address > the U.S. National Research Council's "Grand Challenges" for > environmental science, relies on robust cyberinfrastructure. Streaming > data middleware is an essential component of this cyberinfrastructure, > providing the foundation for reliable data acquisition and instrument > management services. The environmental science and engineering > communities are currently engaged in the early planning and > development phases of the next generation of large-scale sensor-based > observing systems. The Open Source DataTurbine Initiative is a new > NSF-funded project to empower these communities with Streaming Data > Middleware. > > Large-scale sensor-based observing systems face a number of > significant challenges in design and operations, including > heterogeneity of instrumentation and complexity of data stream > processing. These systems incorporate instruments from across the > spectrum of complexity, from temperature sensors to acoustic Doppler > current profilers, to streaming video cameras. They typically require > integration of instruments from various vendors and R&D labs. > Requirements on the cyberinfrastructure include scalable and secure > support for real-time data acquisition, instrument and data stream > management, and analysis and visualization. To address these > cyberinfrastructure challenges in a principled manner, we launched the > Open Source DataTurbine Initiative. > > DataTurbine is a robust open-source streaming data middleware system > that satisfies the core requirements for sensor-based environmental > observing systems. It is relatively mature and has been tested in a > variety of real-world streaming data applications. It facilitates the > development of complex distributed streaming data applications, > including real-time virtual observatories and telepresence > collaboratories. The Open Source DataTurbine Initiative combines > commercial-quality software support with an active and engaged user > and developer community. In this talk we share our vision and invite > domain scientists and developers to join the Open Source DataTurbine > Initiative. We also discuss our experiences and results from > real-world deployments of DataTurbine. Further details about the Open > Source DataTurbine Initiative can be found at: > http://www.dataturbine.org > > > When: Tues 27th Nov 12:00noon > Where: Room A.G.30 > > <<37 sem 271107 Fountain.doc>> > Vicki Smith > Administrative Assistant > Biological Sciences > The University of Waikato > Private Bag 3105 > Hamilton > > Ph 838 4148 > Fax 838 4324 > > -- Web1: http://wand.net.nz/~iam4/ Web2: http://www.jandi.co.nz Blog: http://iansblog.jandi.co.nz

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REMINDER: WLUG meeting tonight!
by Meeting Reminder Bot 25 Nov '07

25 Nov '07

There's a WLUG meeting tonight: ---------------------------------------------------------------------- 7:30pm, TW.2.05 (http://www.wlug.org.nz/TW) 3D desktops.. compiz-fusion and Xgl?

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Linux graphics survey
by Ian McDonald 22 Nov '07

22 Nov '07

Given Monday's topic this is timely. I can't go to the meeting as will be in Auckland :-( http://www.phoronix.com/scan.php?page=article&item=924&num=1 -- Web1: http://wand.net.nz/~iam4/ Web2: http://www.jandi.co.nz Blog: http://iansblog.jandi.co.nz

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REMINDER: WLUG meeting is on Monday
by Meeting Reminder Bot 22 Nov '07

22 Nov '07

There's a Waikato Linux Users Group meeting on Monday: ---------------------------------------------------------------------- 7:30pm, TW.2.05 (http://www.wlug.org.nz/TW) 3D desktops.. compiz-fusion and Xgl?

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Amazon's e-book reader runs Linux
by Ian McDonald 21 Nov '07

21 Nov '07

http://arstechnica.com/journals/linux.ars/2007/11/20/linux-on-amazons-kindl… -- Web1: http://wand.net.nz/~iam4/ Web2: http://www.jandi.co.nz Blog: http://iansblog.jandi.co.nz

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Wireless networking problem
by Leslie Katz 21 Nov '07

21 Nov '07

My wife has as a wireless access point an Apple Airport Express that she uses with her Mac. It's set up with WPA for security. I'm am trying to use the thing as well, but am having difficulties. I have 2 laptops with wireless cards, one running Windows XP Media Centre Edition 2005 and one running Damn Small Linux 4. Generally speaking, the Windows laptop connects automatically to the wap when I boot it up. With the Linux laptop, it's very much hit and miss (with more misses than hits). When the Linux laptop is connecting, I first use wpa_supplicant to connect to the wap, followed by pump to configure the interface and all is well. When the Linux laptop isn't connecting, wpa_supplicant doesn't work and when I scan for waps using iwlist, I get a list of neighbours' unsecured waps, but no reference to the Airport Express. I can have the two laptops sitting side by side, the Windows one happily using the wap, while the Linux one isn't even aware of its existence. I'd be very grateful for any suggestions as to what to do to get the Linux laptop finding the wap reliably. Failing that, I'd be very grateful for a pointer to some site where I'm likely to get help with my problem. Thanks for reading this, Leslie -- Visit http://stumblng.tumblr.com An Australian lawyer's tumblelog about things (some legal, most not) you might otherwise have missed

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Re: [wlug] [nzlug] Laptops sans OS possible:
by Craig Box 19 Nov '07

19 Nov '07

On the subject of cheap Linux laptops, OLPC are currently running a "give one, get one" scheme: http://www.laptopgiving.org/en/give-one-get-one.php. The gist is pay $400US, give one laptop to a developing nation, and get one for yourself. I believe this may be the only way members of the public can get one of these machines, at least initially. Unfortunately it's only available in the USA and Canada. If anyone is interested, I am in Canada at present, and would be happy to deliver one or two on behalf of people in NZ. I'll be back there in early Jan, which should hopefully be just after delivery. Please contact me off-list and I'll see what I can do. Craig

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