by Ron | Jan 14, 2009 | Linux
While trying to run a YUM update on a CentOS server today, I got an error message about my /boot partition being full. I ran a df -h and sure enough, there was only 100k left. (My standard install uses 100MB for the boot partition.)
Here’s what I did to fix it.
rpm -q kernel
That returns a list of installed kernel updates. In my case I had more than 25…
kernel-2.6.9-22.EL
kernel-2.6.9-42.0.8.EL
kernel-2.6.9-42.0.8.plus.c4
kernel-2.6.9-42.0.10.plus.c4
…
kernel-2.6.9-67.plus.c4
kernel-2.6.9-67.0.1.EL
kernel-2.6.9-67.0.1.EL.plus.c4
kernel-2.6.9-67.0.4.plus.c4
kernel-2.6.9-67.0.7.plus.c4
kernel-2.6.9-67.0.15.plus.c4
kernel-2.6.9-67.0.20.EL
To remove some of the older ones, run:
yum remove kernel-2.6.9-42.0.10.plus.c4
or to get several at one time:
yum remove kernel-2.6.9-42.*
I recommend leaving a few of the older ones in case you need to revert one day.
by Ron | Oct 24, 2008 | Linux
This tip is for my friend Scarb. For years I’ve used the Linux command “tail -f” for watching logs… but only recently did I discover its versatility for extracting parts of files.
Need to grab only the last 25 lines of a file?
tail -n 25 somefile.txt
How about the last 200000 bytes redirected to another file?
tail -c 200000 somefile.txt > newfile.txt
by Ron | Oct 20, 2008 | Linux
nano /etc/rc.local
and add
/etc/init.d/zabbix-agent start
by Ron | Sep 15, 2008 | Linux, Mac
Dropbox is a service that allows you to keep files synchronized across multiple machines (and multiple platforms).

Here is some additional info from ars technica.
by Ron | Aug 29, 2008 | Linux
I contributed to a Handbrake forum a while back. Thought you might find it useful too.
This is my evolving script for transcoding DVDs from MacTheRipper.
1) Save the file in a logical place (I keep it in the Movies Folder… same place I rip movies to). It will loop through all titles longer than X.
#!/bin/sh
# usage is ./thisScript.sh minimumDuration SomeDirContainingVIDEO_TS
# duration is set in minutes ("30" equals 30 minutes)
# specify the container directory for the VIDEO_TS directory
# example ./handbrake-longer-than.sh 30 24_SEASON6_D1
#set default path to HandBrakeCLI
PathToHandBrakeCLI=/some/path/to/HandBrakeCLI
if [ "${1}x" = "x" ]; then
echo "Minutes not provided"
exit
fi
if [ "${2}x" = "x" ]; then
echo "VIDEO_TS path not provided"
exit
fi
time=$1
export time
for i in $(find $2 -type d -name VIDEO_TS) ; do
for title in $($PathToHandBrakeCLI -t 0 -i $i -L 2>&1 | grep "has length" | sed 's/sec//' | sed 's/[()]//g' | awk '$8 > (60 * ENVIRON["time"]) { print $3 "-" $5 } ') ; do
#this names the title for the output file
titlenum=$(echo $title | cut -f 2 -d '-')
# you can change the preset or any other variables here
$PathToHandBrakeCLI -i $i -o ${2}-title${titlenum}-appletv.m4v --preset="AppleTV" -2 -T -P -t ${titlenum}
#output example: 24_SEASON6_D1-title1-appletv.m4v
done
done
2) Within the script, set the path to your HandBrakeCLI app on line 9.
3) Don’t forget to run this before trying to execute it:
chmod 777 ./handbrake-longer-than.sh
4) Execute it like this:
./handbrake-longer-than.sh 30 24_SEASON6_D1
Where “30” is the shortest title you want to export and “24_SEASON6_D1” is the name of the folder containing your VIDEO_TS directory.
by Ron | Aug 13, 2008 | Linux
To find what flavor of Linux you’re using:
cat /etc/*-release
To find the version, use:
uname -a