You can interactively set up the ssh and rsh connections using the installer -comsetup command.

Enter the following:

# ./installer -comsetup 

Input the name of the systems to set up communication:
Enter the <platform> system names separated by spaces: 
[q,?] sys2
Set up communication for the system sys2:

  Checking communication on sys2 ................... Failed

CPI ERROR V-9-20-1303 ssh permission was denied on sys2. rsh 
permission was denied on sys2. Either ssh or rsh is required 
to be set up and ensure that it is working properly between the local 
node and sys2 for communication

Either ssh or rsh needs to be set up between the local system and 
sys2 for communication

Would you like the installer to setup ssh or rsh communication 
automatically between the systems?
Superuser passwords for the systems will be asked. [y,n,q,?] (y) y

Enter the superuser password for system sys2: 

     1)  Setup ssh between the systems
     2)  Setup rsh between the systems
     b)  Back to previous menu

Select the communication method [1-2,b,q,?] (1) 1

Setting up communication between systems. Please wait.
Re-verifying systems.

 Checking communication on sys2 ..................... Done

Successfully set up communication for the system sys2