100 GB of Ubuntu uploaded \(ratio: 149\) :-)

Sat Oct 31 09:47:36 +0000 2009

Erug leuke atb docu over de begin tijd van het atb-en: http://www.imdb.com/title/tt0907856/

Sat Oct 31 20:28:04 +0000 2009

My small and very personal comparison between Fedora 11 (which I run on my laptop) and Ubuntu 9.10 which is my main Linux distribution.

1. yum vs apt-get

• yum is a lot slower than apt-get
• why do I need connectivity when using yum search
• Why does yum defaults to ‘N’ (no) when I ask it to install software?

All in all I like apt-get a lot better.

2. Default resolution

• Ubuntu 9.10 configured my EeeBox and monitor out of the box, Fedora 11 didn’t.

3. Plymouth graphical boot

Very nice to see this in Fedora 11, I want this too for Ubuntu. Too bad Ubuntu does not use this in 9.10. It will happen in 10.04 (I heard).

I installed my new laptop with Fedora 11, and I must say that it is a very nice distribution. I’m even contemplating leaving PulseAudio enabled, ‘cause it just works. Unlike ubuntu.

To update my story on the KPN dongle (dongel). I just used it on this laptop and it worked out of the box. The only thing you need to remember is that you need to insert the stick before booting you machine. It will not work if you insert it afterwards. If you observe this rule it will just pop up in NetworkManager.

On my new netbook I wanted to get rid of gdm and just start X right away. I use auto-login anyway so it is a bit stupid to first start gdm and then immediately start X.

So I removed gdm and edited /etc/rc.local to start X:

    su - miekg -c xinit xterm

But this sort of does not work anymore in Ubuntu Karmic. Karmic now uses upstart as an init replacement. So I figured why not write an upstart job that starts X?

I’ve bought a new 11.1" netbook from Asus, this is going to replace my aging 4G Surf (named charm). I’ve named the new one up, so I’m hoping the Large Hadron Collider is up and running soon and discovers a new flavor of quarks - ‘cause I’m running out of names. (strange is already allocated if I ever buy a Mac and run Linux on that, top and bottom just don’t sound right).

Okay, I could not find this in the specs, but I do find this fishy. When querying a Windows DNS server it will give out an authoritative answer (aa bit set), but without an AUTHORITY section.

dig +nocmd +noidentify +multiline @ns5.msft.net. soa hotmail.com

;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;hotmail.com.	IN SOA

;; ANSWER SECTION:
hotmail.com.	86400 IN SOA ns1.msft.net. msnhst.microsoft.com. (
		    2009100802 ; serial
		    1800       ; refresh (30 minutes)
		    900        ; retry (15 minutes)
		    2419200    ; expire (4 weeks)
		    3600       ; minimum (1 hour)
		    )

;; ADDITIONAL SECTION:
ns1.msft.net.	3600 IN	A 65.55.37.62

And it gets worse:

iotop is a very neat tool showing the processes which do the most i/o in a top-like manner.

Again having fun with SLES:

SLES-10:

# rpm -i /tmp/iotop-0.3.2-1.1.x86_64.rpm 
warning: iotop-0.3.2-1.1.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID ee454f98
error: Failed dependencies:
python >= 2.5 is needed by iotop-0.3.2-1.1.x86_64

Goes off and installs SLES-11

SLES-11:

# rpm -i
warning: /tmp/iotop-0.3.2-1.1.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID ee454f98
error: Failed dependencies:
python < 2.6 is needed by iotop-0.3.2-1.1.x86_64

Nooooo!

An unofficial rpm of e2fsprogs installed on a SLES 10 system:

# ldd /sbin/e2fsck 
libdb-4.3.so => /usr/lib64/libdb-4.3.so (0x00002b5e004e2000)
libpthread.so.0 => /lib64/libpthread.so.0 (0x00002b5e006d6000)
libc.so.6 => /lib64/libc.so.6 (0x00002b5e007ef000)
/lib64/ld-linux-x86-64.so.2 (0x00002b5e003c6000)

Now guess what happens when you reboot?

The nss-ldap module allows you to have your user information in a LDAP server. Within the module you can select some options on how to connect to the LDAP server:

• hard, use an exponential back-off when connection, waiting up to 64 seconds before trying a different server.
• soft, when the server is not responding give up immediately.

The problem is, both are insufficient…

With soft you don’t have any benefits for your backup LDAP server. With the hard policy you can failover to the second (or third) server, but when you boot the machine (and it does not have networking) you are stuck with the exponential back-off. This can mean that booting a server can take a couple of hours: every uid lookup will take 64 seconds.

Heb PSP gekocht. Wow! Eindelijk weer leuk gamen.

Sun Sep 27 16:39:19 +0000 2009

Well, as I’m off to The Hague for the rest of the year, I need some kind of Internet in the evening. So off to KPN to get a umts card (or dongel as they call it). For late night gaming I’ve also bought a PSP :-)

Well, to make a long story short: this stuff is hard to get working in Ubuntu. When you insert the dongle it is first seen as a cdrom…, only after you successfully install the Windows software it will become a modem. Who comes up with this kind of crap?

After trying out Zabbix, I’m back to munin and monit for my (small) monitoring needs.

I think the beautiful rrd images of munin are just unbeatable and monit has never let me down; you can easily restart daemons - something I was still configuring in zabbix. And our Ubuntu Certified Professional Course also has a few slides on munin. This was the last push I needed.

I was still a bit rusty so I just followed a howto to do the initial configuration.

Well, a lets-install-kernel-2.6.31-on-Ubuntu-Jaunty turned out to be a bad idea. The kernel install went OK, but my X went poef. No more bitmap fonts. Looks like some bad interaction between the X Intel driver and the new kernel mode settings.

Anyhow, I figured why not upgrade to Karmic? 15 minutes later my desktop system was completely hosed and I was left staring at a GRUB 1.97 menu.

I never knew that the GRUB command line allows you to type

With monit services are restarted, ever since I’ve installed zabbix I wanted the same functionallity. Turns out this is possible, but it takes some configuration.

Also see the zabbix manual, where it gets interesting from page 160 onwards.

In zabbix go to Configuration->Actions.

Add a new ‘Action Operation’ in which you want to run a remote command.

1. Operation type: remote command
2. Remote command: host:script in my (test) case elektron:/home/miekg/bin/zabbix_service {TRIGGER.NAME}: {STATUS}

And zabbix_service is now a shell script which will echo its arguments to a file in /tmp.

The shell (in this case bash) is packed with features. So much so that you will probably never ever learn them all. Brace expansion is one of those things.

What is it? In the bash manual it says:

Brace Expansion

Brace expansion is a mechanism by which arbitrary strings may be generated. This mechanism is similar to pathname expansion, but the filenames generated need not exist

So what is it? You can make your shell generate strings, like so:

Replying to @zmooc

super gave video!

Tue Aug 18 16:14:02 +0000 2009

Just bought anothor EeePC, this time the 900HD variant. Installing Ubuntu as we speak and giving Windows the boot. The 4 minute encounter with Windows XP (which felt like 4 hours) gave me the impression of a fast machine. This was just a quick peek to see if the hardware was working.

Going with Ubuntu 9.04 - then removing Pulseadio and (maybe) upgrading the kernel to 2.6.30.4.

The trick is to disable the hardisk in the BIOS and to disable all quick boot stuff in there too. So that my SD card with the Ubuntu install will boot.

Excellent idea Ton!

How to make a custom filter in git to expand the string $Hash$ to something more usefull, ala the $Id$ (which git already supports), but then with more info (committer, date, etc.).

Which also helped in this case was the Pro Git book which is, as of now, a must buy.

But as always is the case between Ton and me, I find his scripts too long :-) So I miekified his solution.

In Perl you have this:

% perl -e 'print "a" x 5, "\n"'
aaaaa

With that you can easily create a separator string consisting out of 60 spaces.

I always missed this in my shell - until now.

In Zsh have the following expansion:

l:expr::string1::string2:

Pad the resulting words on the left. Each word will be truncated if
required and placed in a field expr characters wide. 

See zsh.dotsrc.org. There is also a r: variant which operates in the same way.

While rechecking my rdup test-suite one of the tests failed. On closer inspection it was due to the following line:

DAY_BEFORE=$(( $(date +%d) - 1 )) 

When $(date +%d) is 10 this yields:

$ DAY_BEFORE=$(( 10 - 1 ))
$ echo $DAY_BEFORE
9

Also with octal values (those starting with a leading zero), it also works:

$ DAY_BEFORE=$(( 06 - 1 )) 
$ echo $DAY_BEFORE
5

So when does this go wrong? When the day is 08 or 09 (as it is today):

A customer wanted some performance figures for a ESX cluster we built. We used our own atop and the trusted workhorse of plotting Gnuplot to make some performance plots.

Creating the data

As said, we used atop for this, it has a nice data gathering mode which prints out lines like these:

13:40:07  cpu   %usr  %nice   %sys  %irq %softirq   %steal  %wait  %idle
13:40:08  all      0      0      0     0        1        0      4     95
13:40:09  all      0      0      1     0        0        0      0	  99

We were interested in the values of %usr, %sys, %irq + %softirq, %wait and %idle.

So you think you know git… today I found out something “funny”. In a git repository:

$ git log
$ fatal: object 1fcc8de9361c56e538ff35d8cc4b07a9c95b7bf3 is corrupted

Okay, WTF? Lets look in the .git directory:

$ cd .git/objects/1f
$ ls -l
total 4
-r--r--r-- 1 root root 1057 2009-06-23 19:03 03db070bcb47bff3f8106f2ec7028b3496aaa8
-r--r--r-- 1 root root    0 2009-08-03 21:41 cc8de9361c56e538ff35d8cc4b07a9c95b7bf3

Ah, 0 bytes, that explains it (probably due to the weird reboot of last night and ext4).

Finally made the switch to jackd which works so much better than Pulseaudio. Ubuntu did not make this easy, but with some perseverance it works. One of the things I really hate about Pulseaudio is that when I click on a new song in audacious it would take about 1 second before the audio stabilized. Also with flash audio would stutter for the first few seconds.

First (if you don’t care about gnome-desktop):

Yes, what a nice post on ssh escape keys.

So you need to press <enter> and then ~ for the escape character to work!

If you ever administered a DNS server you are probably familiar with the IN (internet) class, as in

localhost   IN	    A	    127.0.0.1

where you define an IP address for the name localhost. As you may, or may not, already know there are other classes defined (but hardly used) for the DNS. Two of those are the Chaos class (CH) and the Hesiod (HS) class. With these classes you can create some sort of parallel world where you can also define names. This feature of the DNS isn’t exactly in great use, but is is nice to know where they were used for.

google wave ref impl. is in java... *yech*

Wed Jul 29 11:56:59 +0000 2009

Do I want this?

% ls -ld Joe_Cocker_-_The_Definitive_Collection 
drwxr-xr-x 2 miekg admin 4.0K Jul 20 22:20 Joe_Cocker_-_The_Definitive_Collection/
% cd *joe*
cd: no such file or directory: *joe*
% unsetop case_glob 
% cd *joe*
% pwd
/shared/vol/music/J/Joe_Cocker_-_The_Definitive_Collection

Currently we are building a fairly rock solid high availability cluster for a client. This has the “usual” ingredients: two locations, two NetApps, two clusters of three vmware ESX servers and a bunch of virtual machines running on top of the ESX servers. Also included in the mix is a VDI (now called View) virtual desktop infrastructure for running virtual windows XP clients.

This is all managed by SRM (site recovery manager) and it is almost working. But that is another story.

I’ve told a few times about how to build a library.

But there a some extra things that must be done before you can call yourself a complete librarian.

1. ID-ing the books you have
2. Storing the information
3. Marking the books
4. Sorting and shelving the books
5. Remembering who borrowed what

ID-ing books

For this I bought a barcode reader that reads the ISBN number of the book’s backcover. With book_get (Perl code) I can retrieve the author, title, genre and year published from Google.

I already knew (Open)Solaris sucks, but now Ton has also figured it out.

ZFS definitely does not suck. Why not petition Oracle to GPL(v2) ZFS? Especially now Oracle wants to kill OpenSolaris?