[CentOS] Avoiding mounting other installation's partitions and volumes

OSes: CentOS 5.0 x86, CentOS 4.5 x86.


Hi, I have CentOS 5.0 x86 installed on an IDE HDD.


[john at localhost ~]$ df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       224G  8.5G  204G   4% /
/dev/hdc1              99M   16M   79M  17% /boot
tmpfs                 506M     0  506M   0% /dev/shm



I want to install CentOS 4.5 x86 on another hard disk, but from my past 
experience, when using one installation, it also automounts the logical 
volumes etc of the other installation during boot.

How can I avoid this?