The following is a description of the image group cluster computer.
Current cluster setup
Currently the cluster consists of 3 disk servers and 3 IBM blade servers for computation.
How to use the cluster
Adding new users
Make the user account the first time on imagediskserver1. This should create the home directory. Following this make sure that user ID and group ID is the same on all machines. All users should be in the group 'users' and possible any other relevant groups (e.g. system administrators should be in the group 'wheel').
Example: How to create the user kimstp
On imagediskserver1 as root:
useradd -m -g users -p <crypt output> kimstp
This will create a new account with the name kimstp in the group users with home directory in /home/kimstp.
<crypt output> is the crypt encoded password string. You get it from
the diku system by running the following command on ask (or any other host on the diku internal network):
ypcat passwd | grep -E 'kimstp'
The crypted password is the second string in the ':' separated list.
On the rest of the machines:
Check the user ID in /etc/passwd (number 3 number on the line) on imagediskserver1. Lets assume it is 1100 (don't use the same user ID for all users!!!), then on each machines do
useradd -g users -u 1100 -p <crypt output> kimstp
Alternatively, consider using newusers which is based on a similar format as the passwd file (man 5 passwd).
Adding a user to other groups:
Example: Adding kimstp to the group wheel
usermod -G wheel kimstp
Automatic synchronization of passwords with the diku system
Rune is working on this.
Currently there is no backup of the cluster. The only safety lies in the use of RAID 5 on all disk servers, which in theory should provide tolarance towards one faulty disk per disk server. We are working on a backup solution.