December 2007 Archives

I'd not blogged about this before, but about a month ago, I took the RH436 course, on Red Hat clustering and storage management. I figured that as a requirement for RHCA, this would probably be a good course to start with since I had limited knowledge in the area. I got a brand new (pilot) course, and the instructor of the course was actually the one that wrote it (thanks Marc!). This new course is based on RHEL 5.1, and uses Xen domains for the cluster nodes rather than physical hardware - this should both drive down the cost of the hardware and make it much easier for the students in the class. The main benefit is that the requirement that currently exists for access to remote hardware (either in Raleigh, Stuttgart, or Singapore) will be removed, and more students will be able to take the course. This can't be done right now, since they are not sure that all classrooms will be able to support Xen, have large enough hard drives, etc. So the first parts are in place, restructuring the course such that requirement is strictly no longer there (since FC switches, storage arrays, etc) are not required. Next comes making sure that all of the hardware in the classrooms is actually capable of running the class. For now, though, the remote equipment is still in use.

So, I know what you've been waiting for - the much anticipated score of the exam. RHCA exams take longer to score due to significantly lower volume than the RHCE exams. First, RHCA exams are not offered as frequently or in as many locations as the RHCE exams, and second there are many fewer qualified people to proctor and score them.

Endorsement requirements:
Section  score:                           100

ENDORSEMENT: PASS

Web 2.0 - some videos

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Well, I am on the mailing list for the New York Technology Meetup, and a link to this video just came across the mailing list:

The theme that I really take away from this video is that form has been decoupled from content, whereas in the early days of the Internet, content and form were pretty much inseparable - you didn't have things such a RSS, Atom, iCal, XML, and many other enabling technologies of this revolution. As a direct result of form being separated from content, you have people who would either have no knowledge of or no inclination to setup a website doing just that (such as this blog - I'm focused on content here, not formatting or how to make it all work together - I'll let the creative types deal with that). That's not to say that it would be impossible for me to do, it would simply take much more time out of my busy life to handle than this blog does. Pretty much what I do here is post, check out Google Analytics for the site every few days, maybe check for some problems and where this is in search positioning with Google Webmaster Tools every few days, and that's about it. The latter two are simply because I want to make this more useful for you, my readers (of whom I have a lot more than I thought :) ).

I think that the video does an outstanding job of showcasing the types of things that can be done with Web 2.0 technology, particularly XML and mashups. This blog, for example can be consumed either straight up in the browser, or through your favorite RSS reader, which itself can present the content in various ways.

While researching for this post, I also found a video that is both ominous and humorous at the same time. I'll let the video speak for itself, but suffice it to say that I don't agree with it. Unfortunately, I can't find the video again (seriously). Which leads me to another point, right along the same lines - the Internet is full of information. Everything is miscellaneous. When I saw that video, I could have tagged it on del.icio.us (which link to my bookmarks is in the right hand column if you're reading this on the original website - if not it's here. The information is ours to organize, in a way that is meaningful to us.

Blogger by e-mail

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Blogger has this functionality that allows you to send an e-mail and have it posted to your blog automatically. Generally a really useful feature, but as I found out this evening, the feature works a bit too well sometimes. My e-mail server on my blackberry automatically appends a disclaimer to the bottom of my mail about the information being "confidential and proprietary". Obviously not for stuff that I send to my blog, I want the public to see it. There's a tag that you can put in the e-mail to tell it that it is the of the post, but I forgot to do it earlier this evening. I immediately realized it, and resent the edited e-mail, assuming that an e-mail with the same subject would replace the previous one. Apparently not, and I now have two posts with exactly the same content, minus the disclaimer on one of them. I'll delete the extraneous post when I get home.

That's all that I have to rant about for now :-)
Well, the new Apple store at 14th and 9th opened yesterday. Unfortuantely, I didn't know about it until today, so I couldn't queue up for the grand opening. But I did go there today at least. There's 3 floors to this monstrosity of a store, but it's not the largest in the world - that goes to the Reagent Street store in London. Nor is it the largest in the US - that title goes to Chicago. It also doesn't have the largest Genius Bar - there's one that's four feet longer. With all of these shortcomings, it's still a worthwhile destination. The staircase reminds me of the subteerainian 5th Avenue store - a spiral glass staircase the revolves around a core meant to resemble an iPod. However, the glass elevator in the middle is not to be found here, unfortuantely. I'll try to get back at some time in the near future with my camera in order to get some pics of the place - it's really a quite incredible place that would look out of place anywhere except Manhattan.

Minimal kickstart

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I get a lot of questions regarding the fact that RHEL and CentOS install "too much" by default. They do - not many people require Bluetooth on their servers for example. So here's a kickstart which will install Just enough in order to boot the system. Note that removing some stuff from the below list will result in a less than functional system, possibly even unbootable. There is a bug which could result in the system becoming unbootable if too much is stripped out. Without further ado, here's a working kickstart for CentOS 4. It will also work on RHEL4 if you remove the 'yum' package specification
install
text
reboot
url --url (your install source goes here)
lang en_US.UTF-8
langsupport --default=en_US.UTF-8 en_US.UTF-8
keyboard us
skipx
network --device eth0 --bootproto dhcp
rootpw --iscrypted (insert a crypted rootpw here - openssl passwd -1)
firewall --disabled
selinux --permissive
authconfig --enableshadow --enablemd5
timezone America/New_York
bootloader --location=mbr
# The following is the partition information you requested
# Note that any partitions you deleted are not expressed
# here so unless you clear all partitions first, this is
# not guaranteed to work
clearpart --all --initlabel
part /boot --fstype ext3 --size=250 --ondisk=sda
part pv.2 --size=0 --grow --ondisk=sda
volgroup VolGroup00 --pesize=32768 pv.2
logvol / --fstype ext3 --name=LogVol00 --vgname=VolGroup00 --size=1024 --grow
logvol swap --fstype swap --name=LogVol01 --vgname=VolGroup00 --size=256 --grow --maxsize=512

%packages --nobase
coreutils
yum
rpm
e2fsprogs
lvm2
grub
sysstat
ntp
openssh-server
openssh-clients


%post

# setup NTP
cat << EOF > /etc/ntp.conf
restrict default noquery notrap nomodfiy
restrict 127.0.0.1
server 0.rhel.ntp.org
server 1.rhel.ntp.org
server 2.rhel.ntp.org
driftfile /var/lib/ntp/drift
EOF
chkconfig ntpd on

It looks like some of it got clipped due to the blogger template. However, at least in FF on Windows (which is what I have at work :( ), if you select the whole thing and copy, you get the whole thing. Alternatively, view the page source :)

Linux and AirCard 595U

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I've got a Sierra AirCard 595U from Sprint that I had put off getting working under Linux on my F8 laptop. Well, finally got it working, and it was quite painless, and speeds are good, too: So, how did I do it? Really quite simple - all that you need to do is create a file /etc/wvdial.conf with these contents:
[Modem0]
Modem = /dev/ttyUSB0
Baud = 961600
SetVolume = 0
Dial Command = ATDT
Init1 = ATZ
Init3 = ATM0
FlowControl = NOFLOW
Then after that, you create the ppp peer called 'sprint' by putting the following in /etc/ppp/peers/sprint:
 ttyUSB0
115200
debug
noauth
defaultroute
usepeerdns
connect-delay 10000
user @sprintpcs.com
show-password
crtscts
lock
lcp-echo-failure 4
lcp-echo-interval 65535
connect '/usr/sbin/chat -v -t3 -f /etc/ppp/peers/sprint_chat'
And finally, put the following in '/etc/ppp/peers/sprint_chat':
'' 'AT'
'OK' 'ATE0V1&F&D2&C1&C2S0=0'
'OK' 'ATE0V1'
'OK' 'ATS7=60'
'OK' 'ATDT#777'
After that's done, you can type 'pppd connect sprint', and you'll have a connection!