Apache Subversion

Welcome to subversion.apache.org, the online home of the Apache Subversion™ software project. Subversion is an open source version control system. Founded in 2000 by CollabNet, Inc., the Subversion project and software have seen incredible success over the past decade. Subversion has enjoyed and continues to enjoy widespread adoption in both the open source arena and the corporate world.

via Apache Subversion.

IEEE 802.22

IEEE 802.22 – Wikipedia, the free encyclopedia.

IEEE 802.22 is a standard for Wireless Regional Area Network (WRAN) using white spaces in the TV frequency spectrum.[1] The development of the IEEE 802.22 WRAN standard is aimed at using cognitive radio (CR) techniques to allow sharing of geographically unused spectrum allocated to the Television Broadcast Service, on a non-interfering basis, to bring broadband access to hard-to-reach, low population density areas, typical of rural environments, and is therefore timely and has the potential for a wide applicability worldwide. It is the first worldwide effort to define a standardized air interface based on CR techniques for the opportunistic use of TV bands on a non-interfering basis.

IEEE 802.22 WRANs are designed to operate in the TV broadcast bands while assuring that no harmful interference is caused to the incumbent operation, i.e., digital TV and analog TV broadcasting, and low power licensed devices such as wireless microphones.[2][3][4] The standard was expected to be finalized in Q1 2010, but was finally published in July 2011.[5]

‘Super Wi-Fi’: Super, But Not Wi-Fi

That’s in part because for now, at least, you can’t move a white-space device around. You can’t put a white-space radio into a phone or laptop because each white-space device must check its location against a database to determine which TV channels and wireless microphones are being used in the device’s area, so they can avoid those channels.

via ‘Super Wi-Fi’: Super, But Not Wi-Fi | News & Opinion | PCMag.com.

That may change a few years down the road, when “personal/portable” white space devices appear. Based on the 802.22 standard, these will be chips able to fit into laptops and tablets, with software that can “sense” clear frequencies as they move around.

Two LVM VolGroup’s, same name, one is system disk – what to do?

It’s a lot easier to rename the “old” volume group if the old drive is the only one connected to the system.

Using your first FC4 installation CD and with only the old drive installed, boot into rescue mode (boot: linux rescue), but don’t search for or mount the FC installation. At the command prompt, you will probably need to active the lvm like this:

lvm vgscan

lvm lvscan

lvm vgchange -a y

lvm pvscan

lvm lvscan

The last two commands should list your volume group(s) and logical volume(s). Now use vgrename to fix the problem:

lvm vgrename VolGroup00 whatever_you_want_to_call_it

Note that all lvm commands need to be preceded with “lvm” in rescue mode.

via Two LVM VolGroup’s, same name, one is system disk – what to do?.

Red Hat / CentOS: Swap / Change Ethernet Aliases

Red Hat / CentOS: Swap / Change Ethernet Aliases.

This didn’t work the first time I tried it and now it does.  For some reason eth0 and eth1 get switched on the 64bit CentOS 5.7 build which causes routing problems.  This can also be solved by fixing the static routes in /etc/rc.local.  It bothered me to have these interfaces have different names depending on what OS is running.  I think there’s also a way to force this in /etc/udev/ directory by adding a persistent-net rule file.  It all works now.

BTW: I also changed /etc/sysconfig/hwconf but don’t think that had any effect.