MPICH

Scenarios

This section describes how to run MPICH (version mpich-3.3.2 is used as an example) in a BMS cluster.

Prerequisites

• Password-free login has been configured between BMSs in the cluster.
• MPICH has been installed on all BMSs in the cluster.

Procedure

1. Disable the firewall.
   1. Log in to a BMS in the cluster.
   2. Run the following commands to disable the BMS firewall:

      # service firewalld stop

      # iptables -F

   3. Run the following command to check whether the firewall has been disabled:

      # service firewalld status

      Figure 1 Disabled firewall
      

   4. Log in to all other BMSs in the cluster and repeat 1.b to 1.c to disable firewalls on all BMSs.

2. Modify the configuration file.
   1. Log in to any BMS in the cluster and run the following command to add the hosts configuration file:

      # vi /etc/hosts

      Add the private network IP addresses and hostnames of all BMSs in the cluster. For example, run the following commands:

      192.168.1.138 bms-arm-ib-0001

      192.168.1.45 bms-arm-ib-0002

      ...

   2. Run the following command to add the hostfile file:

      $vi hostfile

      Add the hostnames of all BMSs in the cluster and the number of cores (for example, 2 cores).

      bms-arm-ib-0001:2

      bms-arm-ib-0002:2

      ...

   3. Log in to all BMSs in the cluster and repeat 2.a to 2.b.

3. Run the executable file on a BMS through MPICH.

   $ mpirun -np 2 -hostfile /home/rhel/hostfile /home/rhel/hello

   Figure 2 Successful execution of MPICH in the BMS cluster
   
   

   Specify the path of hostfile when running it. The path of the executable file hello must be absolute. All executable files in the cluster must be in the same directory.