In my previous post of "
How to Install CentOS in VMware Workstation", now I am going to write steps of "
How to Create a Cluster in LinuxOS". The following are the easy steps to create a cluster but be-careful while typing commands because these are case-sensitive and also care about spaces between commands because they also matter.
Now first make a check list of our steps as given below and we start doing these steps...................
1: Linux
Installation in Nodes
2: SSH
equivalence establishment for user root
3: SSH hostkeys
collection
4: Setup NTP
service
5: Installation
of PDSH
6: Setup NFS
(Optional)
7: Creation of
ordinary user, and also setup SSH equivalence for that
8: Installation
of prerequisite packages (GCC, G77 etc)
9: Installation
of MPI
10: Compiling
Linpack (Optional)
Step 1:
Installation
of Linux on all nodes
Step 2:
Working
on Master Node
Start with hosts file
Vi /etc/hosts
127.0.0.1 localhost.localdomain
localhost
10.0.0.20 masternode
10.0.0.21 node1
10.0.0.22 node2
Copy Hosts file on node1 and node
For Node1
Scp /etc/hosts node1:/etc/
Are you sure you want to continue connecting (yes/no)? yes
Node1 Password will be required
For Node2
Scp /etc/hosts node2:/etc/
Are you sure you want to continue connecting (yes/no)? yes
Node2 Password will be required
Step 3:
Key
Generation Process
ssh-keygen –t dsa
Just press enter on all steps
ssh-keygen –t rsa
Just press enter on all steps
Go on the directory and verify the generated keys files
cd .ssh/
ls –l
Following files has been generated:
id_dsa
id_dsa.pub
id_rsa
id_rsa.pub
known_hosts
Generate authorized_keys in ssh directory
cat *.pub >> authorized_keys
Copy these files on Node1 and Node2
cd ..
For Node1
scp –r .ssh node1:/root/
Node1 Password will be required
For Node2
scp –r .ssh node2:/root/
Node2 Password will be required
Generate Nodes ssh finger prints (Not need for mpiuser)
ssh-keyscan –t dsa masternode node1 node2 >
/etc/ssh/ssh_known_hosts
ssh-keyscan –t rsa masternode node1 node2 >>
/etc/ssh/ssh_known_hosts
Now you can view the generated file using
less /etc/ssh/ssh_know_hosts
Copy this file on Node1 and Node2, Note that will not ask
for the password this time because the public key has already attached or
certify on the other side.
scp /etc/ssh/ssh_known_hosts node1:/etc/ssh/
scp /etc/ssh/ssh_known_hosts node2:/etc/ssh/
Now test with login on the other nodes
ssh node1
Run the command on other nodes
ssh node1 uptime
Step 4:
Setup NTP
service
vi /etc/ntp.conf
disabled the following lines:
#server 0.fedora.pool.ntp.org dynamic
#server 1.fedora.pool.ntp.org dynamic
#server 2.fedora.pool.ntp.org dynamic
enabled the following lines:
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 10
service ntpd restart
shutting down ntpd: [FAILED]
starting ntpd: [OK]
ntpq –p –n
Step 5:
Installation
of PDSH (pdsh-2.18-1.src.rpm)
Recompile it
rpmbuild --rebuild pdsh-2.18-1.src.rpm
change directory
cd /usr/src/redhat/RPMS/i286/
rpm –ivh pdsh-*
vi /etc/machines
masternode
node1
node2
pdsh –a date
pdsh –a ntpq –p –n
Step 6:
Setup NFS
vi /etc/exports
/cluster ^(rw,no_root_squasn,sync)
service nfs restart
chkconfig --level 35 nfs on
pdsh –a mkdir /cluster
service nfs restart
mount –t nfs masternode:/cluster /cluster/
df –hT
vi /etc/fstab
At the end of this file, add following line:
Masternode:/cluster /cluster nfs defaults 0 0
Step 7:
Creation
of ordinary user, and also setup SSH equivalence for that
[group: mpigroup-600, user: mpiuser-600, member of mpigroup,
/cluster/mpiuser]
groupadd –g 600 mpigroup
useradd –u 600 –g 600 –d /cluster/mpiuser mpiuser
perform above commands on all nodes
Step 8:
Installation
of prerequisite packages (GCC, G77 etc)
rpm –q gcc
rpm –qa | grep g77
yum list | grep g77
yum –y install compat-gcc-34-g77
pdsh –w node1, node2 yum –y install compat-gcc-34-g77
Step 9:
Installation
of MPI
su – mpiuser
generate ssh keys repeat step-3
Download MPI from
(http://www.mcs.anl.gov/research/projects/mpich2/downloads)
Mpich2-1.0.8.tar.gz and copy on cluster directory
Goto on root user and execute the following commands:
chown mpiuser:mpigroup /cluster –R
goto cluster directory using mpiuser
Unzip the following mpi file
tar xzf mpich2-1.0.8.tar.gz
cd mpich2-1.0.8
./configure --prefix=/cluster/mpich2
make
make install
setup some environment variables
Goto Home Directory
cd
vi .bash_profile
PATH=$PATH:$HOME/bin:/cluster/mpich2/bin
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/cluster/mpich2/lib
export PATH
export LD_LIBRARY_PATH
source .bash_profile
echo $PATH
which mpd
which mpiexec
which mpirun
cat >> /cluster/mpiuser/mpd.hosts << EOF
> masternode
> node1
> node2
vi /cluster/mpiuser/mpd.hosts
remove the masternode and save it
vi /cluster/mpiuser/.mpd.conf
secretword=redhat
mpd &
chmod 0600 /cluster/mpiuser/.mpd.conf
ps aux | grep mpd
mpd &
mpdtrace
mpdtrace –l
mpdallexit
mpdboot –n 2 –chkuponly
mpdboot –n 2
mpdtrace
For checking that your cluster is successfully created run the following example
cd /cluster/mpich2-1.0.8/examples
mpiexec –n 3 ./cpi
how to compile the program of MPI
mpicc –o icpi icpi.c
Now we have successfully created the cluster on CentOS which we have installed in VMware. Now you are able to perform your codes in virtual machines.
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