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    Creative Commons License
    This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
    PyBlosxom

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    Wed, 17 Dec 2008


    /xLife/China/Beijing/OpenSource: Open Source in Beijing

    Organizations:

    Beijing Java User Group (BJUG): http://www.bjug.org/
    Matrix: http://www.matrix.org.cn/

    Beijing Linux User Group (BLUG): http://www.beijinglug.org/

    Beijing Python User Group (BPUG): http://groups.google.com/group/bpug/

    Drupal China: http://drupalchina.org/

    Open Party: http://www.beijing-open-party.org/
    Organizer / aggregator for Open Source events.

    Companies:

    Exoweb: http://www.exoweb.net/
    An Open Source software development company, with a 100% Open Source working environment.

    Novell: http://www.novell.com/
    Rm 3603, Beijing Fortune Plaza Office Tower A,
    #7 East Middle 3rd Ring Road, Chaoyang District (just north of Guomao)
    Projects: Mono Accessibility, OpenSUSE

    Sun Microsystems: http://www.sun.com/
    Technology Plaza center, Tsinghua Science Park
    Chengfulu, Haidian District (just west of Wudaokou)
    Projects: OpenSolaris

    posted at: 21:59 | path: /xLife/China/Beijing/OpenSource | permanent link to this entry

    Tue, 16 Dec 2008


    /Linux/Debian/WPA: Easy wpasupplicant on Debian

    A little poking around revealed that this file /usr/share/doc/wpasupplicant/README.Debian.gz was the secret sauce for getting wpasupplicant painlessly functioning on a Debian machine.

    Like with wireless-tools, Debian has integrated wpasupplicant into the /etc/network/interfaces file.

    To talk to a simple WEP-encrypted access point, this is the stanza I am using in /etc/network/interfaces:

    auto eth1
    iface eth1 inet dhcp
       wpa-ssid linksys
       wpa-key-mgmt NONE
       wpa-wep-key0 8453017892
       wpa-wep-tx-keyidx 0
    

    To achieve the same with wireless-tools instead, I have this stanza:

    iface home inet dhcp
       wireless-channel 11
       wireless-mode managed
       wireless-key 8453017892
       wireless-essid linksys
    

    and of course, "ifup eth1" and "ifup eth1=home" will both connect, the former using wpasupplicant and the latter using wireless-tools.

    Of course, the whole point of wpasupplicant is to talk to a WPA-encrypted access point. Stay tuned until I get a chance to try it again....

    posted at: 03:10 | path: /Linux/Debian/WPA | permanent link to this entry

    Mon, 15 Dec 2008


    /Admin/virtualization/virtualBox: Windows XP Networking Broke

    The last time I started Windows, networking suddenly did not work. (And may have been fall-out from a preceding failed attempt at installing OpenSolaris, during which I was messing with network settings.... I do not know the cause, and did not feel like debugging it.)

    I track Debian testing, and was able to find a slightly newer version of virtualbox in Debian experimental. After upgrading, Windows XP networking came back.

    The newer ("experimental") version of virtualbox is a little bit messed up though. Before, I would always get a nice clear prompt to manually load the vboxdrv kernel driver on startup. Now I am getting some weird message about running an /etc/init.d/ script that does not even exist. However, merely running:

    modprobe vboxdrv

    still does the trick for getting virtualbox started, just like before.

    posted at: 07:02 | path: /Admin/virtualization/virtualBox | permanent link to this entry


    /Admin/virtualization/virtualBox: File Sharing Between VirtualBox Virtual Machines and Host OS

    Today I bumped into a VirtualBox article[1] that spoon-fed me the file sharing setup for a Windows guest:

    1. In my host OS (Debian Linux) I created a "share" folder called "/scratch/virtualBoxShare".
    2. I then added this folder to the "Shared Folders" for my Windows XP vm on the VirtualBox control window.
    3. After booting into Windows XP, run this command in a Windows terminal: "net use x: \\vboxsvr\virtualBoxShare".
    4. Windows responds with "command completed successfully", and "x:" appears as a "network drive" in "My Computer".

    I do not agree with the statement in this article[1] that at least one Gig of RAM is required to run Windows XP as a guest under Linux. One Gig may be a reasonable amount if you want to use Windows XP hard with multiple open applications, but right now I have a total of 640 Meg, of which I have assigned only 250 Meg to Windows XP. That is enough to run Internet Explorer.

    [1] http://www.linux.com/feature/148194

    posted at: 06:54 | path: /Admin/virtualization/virtualBox | permanent link to this entry

    Fri, 12 Dec 2008


    /Security/circumvention: Penetrating Firewalls, Internet Censorship, and Eavesdropping

    I just bumped into another interesting site called "Circumvention Tools[1]", which has a nice summary of ways to regain access to blocked / censored websites and prevent others from eavesdropping on things you say and places you go while online.

    Of course Tor[2][3], which provides penetration and privacy, and is one of my personal favorites, gets prominent mention. (And surprise surprise, the Tor website is blocked from where I am sitting right now in P.R.China....) Tor in combination with Firefox and the Firefox torplugin, which allows the Firefox proxy through Tor to be turned on and off with a click of the mouse, is incredibly convenient.

    However, Tor can be really quite slow because not enough Tor users agree to operate exit nodes. So I was intriqued to read about how easy it is to set up a SOCKS proxy[4][7] with SSH. This does require that you have SSH access to another machine outside the network where you are being blocked / spied upon, but that is not so hard. Running a machine at home with dynamic DNS[5] is not too hard in most places (where I live its actually not so easy....) And low-end Virtual Private Servers can be had for as little as US$8 per month[6].

    And finally, in the category of "simple tricks[8]", there are services that will e-mail website content to you in response to an e-mailed request. This strikes me as having other interesting applications beyond penetration.... How about a weather e-mail every morning, with a little help from cron? Or pulling down a site in a very bad / slow network environment?

    [1] http://en.flossmanuals.net/CircumventionTools/
    [2] http://en.flossmanuals.net/CircumventionTools/TorTheOnionRouter
    [3] http://www.torproject.org/
    [4] http://en.flossmanuals.net/CircumventionTools/SSHTunnelling
    [5] http://blog.langex.net/index.cgi/Admin/dynamicDNS/
    [6] http://blog.langex.net/index.cgi/Hosting/
    [7] http://en.flossmanuals.net/CircumventionTools/ConfiguringSocksProxies
    [8] http://en.flossmanuals.net/CircumventionTools/SimpleTricks

    posted at: 09:39 | path: /Security/circumvention | permanent link to this entry

    Thu, 04 Dec 2008


    /Linux/Awesome: Introduction to the "Awesome" Window Manager

    I recently made the switch to Awesome mainly because of some ongoing pain in my right arm, which I am attributing to "mouse abuse". So I installed Awesome, which promises to be keyboard-centric rather then mouse-centric, and unplugged my mouse.

    A few days later, so far so good, with some reservations. I certainly do use the mouse less, as the Awesome keyboard shortcuts do make it very convenient to jump around between windows / applications. A bonus feature is more efficient use of screen real estate, as Awesome by default does not have window title bars, and its automatic window layouts are oriented toward displaying all windows at the same time, side-by-side. Though where appropriate, for some applications, you can choose to stack windows on top of one another, and you do get to choose which windows display together. And for many applications, I find myself using them now full-screen all the time, in their own workspace, without a title bar. Firefox, for instance, really seems to display a lot more on one screen (my laptop LCD is a smallish 1024x768).

    Reservations?

    I still use my laptop stick-mouse more then I would like. For certain activities with certain kinds of applications (browsing on a web browser, for instance) there is no way to get away from the mouse. At least I have not found one. For the part of your day you spend dealing with text, though (programming in terminals? writing this blog?) Awesome can almost completely eliminate mouse use.

    Awesome, by default, heavily depends on using the "Windows" key found on many keyboards. My Thinkpad X24 does not have one. The commonly made suggestion is to let the "Alt" key take-over this duty, my changing all instances of "Mod4" to "Mod1" in ~/.awesomerc. It works, but.... many common tabbed apps like Firefox are setup to use Alt-n to switch between tabs. Since Awesome has taken over the Alt key, I must use the MOUSE now to switch between tabs. Yuck.

    posted at: 23:22 | path: /Linux/Awesome | permanent link to this entry

    Wed, 03 Dec 2008


    /Admin/virtualization/VMware: How to Setup VMware on Debian Lenny and Fedora 9

    First download the VMware Server installer[1]. They provide RPMs and tarballs, however the RPM did not work for me on Fedora 9. So it was a tarball install on both machines.

    There are just two scripts to run:

    vmware-install.pl
    vmware-config.pl

    after which the VMware Server was running and ready to go (and set to auto-start after reboots). The config script found it necessary to build kernel modules on both machines, so take note that it must be re-run after every kernel change.

    The VMware Server controls should now be available at:

    http://localhost:8222/

    where the login id is "root" and the password is the same as the host OS. In the case of the Fedora machine, login timed out because of SELinux interference[2]. Removing SELinux made this problem go away.

    Now unzip any Virtual Machine you care to run into

    /var/lib/vmware/Virtual Machines

    on the host. In the VMware Server control center, add the machine, and power it on. Provided you accepted the default Bridge network during VMware Server installation, the Virtual Machine should use DHCP and get its own IP address. The machine I installed was Project Open[3], which provides a web interface. To find the machine's IP address, I used the VMware Server control center console to open a terminal in the machine and issue an ifconfig. After that, pointing a browser at the IP brought up the Project Open greeting page.

    [1] http://www.vmware.com/products/server/
    [2] http://communities.vmware.com/thread/151715
    [3] http://www.project-open.org/

    posted at: 06:44 | path: /Admin/virtualization/VMware | permanent link to this entry