What to change after cloning a Linux server?

Question

Let's say I'm cloning a virtual machine containing a Linux server.

What would you advice to change in the clone? I know - it's kind of vague and depends on what services ware installed on linux but maybe you can throw some ideas?

Right now I change:

• MAC addresses of virtual interfaces [in fact VMware does it for me]
• re-generate SSH certificates [including host certificates - /etc/ssh_host* in the Debian world]
• change the hostname

What more?

Answer 1

• root password change is implied with the "ssh certificates change", I guess
• other certificates: Mail TLS/SSL, Webserver (Apache?) SSL, known-hosts ssh files, other authentification information (Backups? cron-jobs? fetchmail? FTP and ftpd? special repositories (Debian)?
• ip address and routing information (well, depends on the location of the vm, sounds like you just cloned a vm which stays at the same Host-system so it might not be relevant here)
• monitoring: snmpd credentials, maybe automatic data-gathering from other systems?
• add/remove users (and/or their passwords/home-dirs/...)
• Backup procedure
• documentation ;)

You also might want to set on other systems: reverse-dns entries, dns/static routes, update firewall, update central monitoring/syslog...

Answer 2

1- Change root password for better security ?

Answer 3

sys-unconfig (in RHEL) will do it all for you