Exadata Cell customizations

Exadata Cells are not allowed for customizations, only Exadata Compute Nodes are allowed.
(the reason as you all know is that; disk accesses with special CELL software has a major effect for performance mystery of exadata. )
But we made some small customizations on CELLs due to company policies and asked Oracle.
Their answer is below.
we made 3 config changes, 1 was rejected (so we rolled-back), but other 2 was OK.

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- you did not make any package install/update/uninstall, it is OK.
- You must again note that, all permitted customizations are your responsibilities as they will be lost after each image upgrade.
- Answers for each config is written below

- This config causes no support issue because it creates neither dependency nor side-effect for cell software.

# cat /etc/logrotate.d/rootmail
/var/spool/mail/root {
    missingok
    notifempty
    compress
    size 1G
    daily
    start 0
    rotate 1
    create 0600 root root
}
#

- This config is unsupported because it creates additional communication dependency to another server.
- CELL servers must totally be independent. 

# grep 1.2.3 /etc/rsyslog.conf
*.info;auth.*;mail.*;cron.*;local7.none @1.2.3.4:514
#


- This config causes no support issue because it creates neither dependency nor side-effect for cell software. 
- This config removes 10 minutes password lock-time, this is a security caution against dictionary attacks but you may prefer disabling, risk is yours.

# grep lock_time /etc/pam.d/*
/etc/pam.d/login:#auth       required     pam_tally2.so deny=5 onerr=fail lock_time=600 serialize
/etc/pam.d/sshd:#auth       required     pam_tally2.so deny=5 onerr=fail lock_time=600 serialize
#