Yet Another Linux Blog

Treehugger has a story talking about the over-use of the word. “sustainability” seems to be going the way of “green” and “organic”, vague feel-good terms without a specific definition.

I started this blog in the beginnning with the intent of writing about “sustainable computing”, but of course, that is a meaningless term, thus the number of posts I’ve written on the topic (0).

If you go with the classic definition of “sustainability”

Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

then computing as we know it today cannot be sustainable until all of the components of our computing environment are fully recyclable and do not use more energy than necessary. OTOH, today’s dirty wasteful computers are a very valuable tool that can be used towards a “sustainable” goal.

I’ve always used the excellent Free Software called DBAN to erase old hard drives before either giving them away or recycling them. DBAN complies with the government regulations that are designed to prevent data recovery, without destroying the hardware itself. GNU Shred can do the same on the file level, if you want “secure erase file” functionality.

The general belief is that bits can be recovered from the drive, in theory, even after being overwritten with zeros, because of some remaining magnetic forces or something like that. So if a foreign govt is after your data, better safe than sorry and melt that thing down.

In practice, though, the established data recovery companies probably have more advanced technology than the govt. And I’ve used DriveSavers and the like to recover data off dead HDs. I think once it was fried electronics, and another time a bad motor or something. At $2k per disk, it was not cheap, but they got the data back. Of course, in both cases, it was hardware failure that prevented me from reading the drives, and not any deliberate erasure of the data.

So I was surprised to learn that there isn’t a data recovery company that can get your data back if you go and overwrite it with some zeros. Here’s an active challenge: http://16systems.com/zero/

So I guess this means I no longer need to make a DBAN CD when erasing disks, but any LiveCD at all will do just fine.

Aim for feature parity with Windows Home Server. Aim for lower price.

Need to spend more time on differentiating the exact goals. WHS has many more features than a Drobo and yet even getting Drobo-level functionality is tough with Ubuntu (specifically hot-swap drives and online resizing). Try to explain ‘resize2fs’ syntax to your parents

One advantage over Drobo is the FS size limitations: http://www.drobospace.com/blog/entry/11516/Q-amp-A-About-Using-Drobo-s-Large-Volume-Sizes/

Another advantage over Drobo is performance.

An advantage over WHS? That’s a tough one. However, WHS is not designed for use with Ubuntu desktops. So it’s more like “WHS is great given everyone is using Windows.” Just like Time Machine and Time Capsule are awesome if you’re already using a Mac. UHS needs to be great _given_ that everyone is using an Ubuntu machine already. Centralized file store, centralized backups are key.

I already have one previous post about GNU Screen, but I came across a couple of more good tutorials:

• From 2004: GNU Screen: an introduction and beginner’s tutorial
• From 2009: Speaking UNIX: Stayin’ alive with Screen

The screen-users mailing list looks to be an excellent resource as well.

source: forum post

1. Insert DVD
2. run ‘vobcopy -m’
3. run ‘HandBrakeCLI -i /path/to/output/of/vobcopy -o movie.mp4 -e x264 -b 2000 -B 192′
4. play movie.mp4

Of course, you’ll need vobcopy and libdvdcss and HandBrakeCLI installed. On Ubuntu, vobcopy is available from the standard repo, libdvdcss can be installed per the RestrictedFormats wiki page and HandBrake is available from their site.

I’m reading “Learning Perl, 5th Ed”.

520 perl -e ‘chomp(@lines=); foreach $i(@lines) {print $i . “\n”;}’ < /var/log/aptitude
523 perl -e 'chomp(@lines=); foreach $i(@lines) {print $i . “\n” unless $i =~ /UPG*/;}’ < /var/log/aptitude
524 perl -e 'chomp(@lines=); foreach $i(@lines) {print $i . “\n” if $i =~ /UPG*/;}’ < /var/log/aptitude
527 perl -e 'chomp(@lines=); @lines2 = reverse(@lines); print @lines2; print “\n”;’
529 perl -e ‘@names=qw(fred betty barney dino wilma pebbles bamm-bamm); print “Enter numbers separated by newlines, then Ctrl-D: “; chomp(@lines = ); foreach $num(@lines){print $names[$num];} print “\n”;’
534 perl -e ‘chomp(@in=); @sorted = sort @in; foreach $i(@sorted){print $i . “\n”;}’

I set my MTU on my Linux box to 1454 instead of the default 1500. Not much of a difference, but maybe it helps

One explanation here: http://www.mynetwatchman.com/kb/ADSL/pppoemtu.htm

Now if I tracepath some place on the Internet, my pmtu doesn’t get dropped down from 1500 to 1492 at my DSL router.

I came across this utility when I was looking to find out how to check what wireless channel I’m using on this Macbook. original post on osxdaily.com

sudo ln -s /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/sbin/airport

Here’s what I see at my current location! Do an -h to see more options.

acbook:~ chekh$ sudo airport -s
SSID BSSID RSSI CHANNEL SECURITY (auth/unicast/group)
linksys 00:18:f8:1b:26:86 -61 6 NONE
OCEANA 00:21:29:c5:bc:3f -84 1 WPA(PSK/TKIP/TKIP)
NETGEAR 00:1b:2f:ff:c9:78 -92 1 NONE
love 00:18:39:97:87:2d -82 1 WPA(PSK/TKIP/TKIP)
7B 00:1e:e5:70:87:fb -59 6 WPA(PSK/AES,TKIP/TKIP) WPA2(PSK/AES,TKIP/TKIP)
07FX09012458 00:12:0e:8b:84:86 -86 6 WEP
AwesomeNet 00:1c:10:90:03:2a -94 6 WPA(PSK/TKIP/TKIP)
green 00:1a:70:80:87:a9 -89 6 WPA(PSK/TKIP/TKIP)
linksys_SES_42059 00:1a:70:4d:eb:5f -96 6 WPA(PSK/TKIP/TKIP)
08FX05004778 00:18:3a:aa:17:c2 -95 6 WEP
Malik 00:1e:e5:b1:df:91 -87 6 NONE
08FX04057630 00:18:3a:a7:7b:07 -95 6 WEP
VASYA 00:0f:b5:69:6f:70 -83 11 WPA(PSK/TKIP/TKIP)
lion 00:17:3f:9f:8b:52 -84 11 WEP
OUTPOST 00:14:6c:f5:d7:36 -82 11 NONE
dlink 00:21:91:08:18:75 -85 4 WPA(PSK/TKIP,AES/TKIP) WPA2(PSK/TKIP,AES/TKIP)
Bronstein 00:18:39:f5:cc:85 -90 8 WPA(PSK/TKIP/TKIP)
FINE 00:13:10:c9:ae:02 -86 10 WEP
macbook:~ chekh$ sudo airport -I
agrCtlRSSI: -60
agrExtRSSI: 0
agrCtlNoise: -99
agrExtNoise: 0
state: running
op mode: station
lastTxRate: 54
maxRate: 54
lastAssocStatus: 0
802.11 auth: open
link auth: unknown
BSSID: 0:18:f8:1b:26:86
SSID: linksys
MCS: -1
channel: 6


Law prof and cop agree: never ever ever ever ever ever ever talk to the cops about a crime, even if you’re innocent: http://boingboing.net/2008/07/28/law-prof-and-cop-agr.html

Upgrading to Sun Grid Engine 6.2 - Keeping the old cluster: https://slx.sun.com/1179271114

IP Visualiser: http://it.slashdot.org/comments.pl?sid=1069911&cid=26197769


alex@asdf:~$ ping google.com
PING google.com (74.125.45.100) 56(84) bytes of data.
64 bytes from yx-in-f100.google.com (74.125.45.100): icmp_seq=2 ttl=242 time=1035 ms
64 bytes from yx-in-f100.google.com (74.125.45.100): icmp_seq=5 ttl=242 time=190 ms
64 bytes from yx-in-f100.google.com (74.125.45.100): icmp_seq=6 ttl=242 time=49.4 ms
64 bytes from yx-in-f100.google.com (74.125.45.100): icmp_seq=8 ttl=242 time=56.6 ms
^C64 bytes from yx-in-f100.google.com (74.125.45.100): icmp_seq=9 ttl=242 time=93.0 ms

--- google.com ping statistics ---
9 packets transmitted, 5 received, 44% packet loss, time 8045ms
rtt min/avg/max/mdev = 49.418/284.939/1035.372/378.558 ms, pipe 2