More than 2 kernels when yum updating

By default, when doing yum updates, only 2 kernels remain after the update. Example, current kernel that you are running and the new updated kernel with any existing kernel versions being removed. Sometimes you might want more than 2 kernels, for testing or any other reasons. To enable more kernals, simply edit the following line to the /etc/yum.conf file:

installonly_limit=2

to read

installonly_limit=10

Where the 10 represents the number of maximum number allowed, in the case above, I set the maximum number to 10.

Therefore, the /etc/yum.conf file should look something like:

[main]
cachedir=/var/cache/yum
keepcache=0
debuglevel=2
logfile=/var/log/yum.log
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
metadata_expire=1800
installonly_limit=10

# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d

Metacity

Metacity is the GNOME2 window manager that comes with Fedora Core. If you find it's window placement policy annoying (i.e. application windows not appearing on the current Xinerama screen with the mouse pointer, but on another one), then http://www.vislab.uq.edu.au/research/accessgrid/software/fedora/related/ provides a fix.

Desktop Sharing (KDE Only)

Enabling Desktop Sharing is quite valuable as it can allow other people to remotely take control of your computer. This is useful as it can allow people more experience that yourself to access your desktop and control the computer themselves. For example, if you are having trouble setting up your Venue Client, you could have someone else remotely connect and show you how to do it. Additional, as a system adminstrator you can start-up the AccessGrid remotely.

To allow Desktop Sharing, click on the start menu and select “Control Center”.

Now click on the “Internet & Network” and then select “Desktop Sharing”.

You can now configure Desktop Sharing. You should select the following options.

Allow uninvited connections. Enabling this allows people to connect without having to manually invite them to each session.
Announce service on the network. Enabling this causes the system to display a message whenever someone takes connects to the machine.
Confirm uninvited connection before accepting. By unselecting this option, the user can automatically bring up the desktop, without any intervention from the machine you are trying to connect to.
Allow uninvited connections to control the desktop. Enabling this allows an uninvited user to control you desktop. Without this option enabled, a remote user can only see what is happening, they can’t actually affect anything.
Input a password. Enabling this ensures that only people who know your password can access your computer.
Click on the "Apply" button and Desktop Sharing has now been enabled.

Killall AG script

There may be times when the AG software “hangs” or it doesn’t shutdown correctly. Therefore, the following script can be used to “kill” Access Grid related processes. This script may also be useful if there are “zombie” AG processes still running which prevent the Venue Client from Starting.

Start up "Terminal". Create a file called ag-kill.sh and edit it. To do this type "vi agkill.sh". You then need to type the following into the file. When you are finished, hit the "esc" key, type ":wq" then hit the enter key to save and exit:

#!/bin/sh

TARGETS="VideoConsumerService VideoProducerService VideoService AudioService rat-4 vic rat VenueClient"

for target in $TARGETS

do

for p in `ps -ef | grep ${target} | grep -v grep | awk '{ print $2 }'`

do

kill -KILL $p

done

done

You then need to change the permissions of the file to make it executable. To do this, execute the command chmod 755 agkill.sh
To execute this script, simply execute ./agkill.sh

Note, do not use this script to shutdown the Access Grid software normally, because if you are using a multi-node setup and you use this script to shutdown the AG software, node services such a VideoProducers will still be running on other machines that make up the Access Grid node.

Additionally, is might be useful to make a shortcut to this script and place it on the desktop.

Disabling the YUM-Update Notifier

There may be cases in which you may not wish the YUM-Update to notify you of available updates… This might be especially important on a production machine, where you don’t want any distractions or standard users thinking they need to update the machine and potentially “break” it.

To prevent the notifications, you will need to start a terminal session as root or “super-user” and execute the following commands:

service yum-updatesd stop

chkconfig --level 2345 yum-updatesd off

The first command will turn off the service. The second command will disable the service, at the run levels 2,3,4 and 5, if the machine is restarted.