Oracle Database Discussions

Hello,
I'm going to configure an AIX cluster (in the sense of HACMP) with Oracle 11gR2 (11.2.0.3).
OS is AIX 7.1 TL1 SP5
PowerHA SystemMirror will be 6.1 SP8

Due to scheduling constraints (and second node arriving only several weeks after the first one) we had to start with one node in a standalone way so we proceeded with Oracle installation and instance creation, configuration and test.
At the moment hacmp filesets are not instaled yet.
then arrived the second node and installed the same way.

As AIX requires rootpre.sh to be executed, it gave followig output:

./rootpre.sh
./rootpre.sh output will be logged in /tmp/rootpre.out_12-08-08.15:04:18

Checking if group services should be configured....
Nothing to configure.

Now we have done the same with the second node and are ready to start with OS filesets related to cluster.
My question is: do I have to re-execute roopre.sh? Any danger or any caveats/tips for rerunning it or any part of it?

For example on a AIX 5.3 cluster where hacmp was already configured I received in a previous installation of 11gR2 this sort of output
servername:root:/> /oracle/stage/11203/database/rootpre.sh
/oracle/stage/11203/database/rootpre.sh output will be logged in /tmp/rootpre.out_12-01-31.10:14:10

Configuring Asynchronous I/O....
Asynchronous I/O is already defined

Configuring POSIX Asynchronous I/O....
Posix Asynchronous I/O is already defined

Checking if group services should be configured....
Please confirm your Oracle Clusterware Userid is a member of the group: hagsuser
Configuring HACMP group services socket for possible use by Oracle.

But from AIX 5L to AIX 7 many things changed, so probably the checks are different based on OS version.
And the script seems not so user friendly....

On my AIX 7.1 system I get this related to Async I/O at the moment
newserver:root:/> ioo -a
aio_active = 1
aio_maxreqs = 131072
aio_maxservers = 30
aio_minservers = 3
aio_server_inactivity = 300
j2_atimeUpdateSymlink = 0
j2_dynamicBufferPreallocation = 16
j2_inodeCacheSize = 200
j2_maxPageReadAhead = 128
j2_maxRandomWrite = 0
j2_metadataCacheSize = 200
j2_minPageReadAhead = 2
j2_nPagesPerWriteBehindCluster = 32
j2_nRandomCluster = 0
j2_syncPageCount = 0
j2_syncPageLimit = 16
lvm_bufcnt = 9
maxpgahead = 8
maxrandwrt = 0
numclust = 1
numfsbufs = 196
pd_npages = 65536
posix_aio_active = 0
posix_aio_maxreqs = 131072
posix_aio_maxservers = 30
posix_aio_minservers = 3
posix_aio_server_inactivity = 300

Thanks in advance for any insight.

Gianluca