When planning a partition scheme, it is advisable to consider creating separate partitions for some directories that may contain large amounts of data, have different backup or security requirements, or benefit from being on different filesystems. Some of the common directories that could be considered for separate partitions are:

/home: This directory contains the personal files and settings of the users. Creating a separate partition for /home can make it easier to backup, restore, or upgrade the system without affecting the user data. It can also improve security by allowing different mount options such as noexec or nosuid. Additionally, it can help to prevent the system from becoming unusable if the users fill up their disk space with personal files123.

/var: This directory contains variable data such as logs, caches, spool files, databases, and web server content. Creating a separate partition for /var can prevent the system from crashing or becoming unresponsive if the /var partition fills up due to excessive logging or caching. It can also improve performance by allowing different filesystem options such as noatime or nodiratime. Furthermore, it can enhance security by isolating the data that may be modified by external sources such as web applications or mail servers124.

/opt: This directory contains optional software packages that are not part of the standard distribution. Creating a separate partition for /opt can make it easier to manage, backup, or remove these packages without affecting the rest of the system. It can also allow different filesystem types or features that may be required by some of the software installed in /opt125.

Other directories that could be considered for separate partitions are /boot, /tmp, /usr, and /srv, depending on the system requirements and preferences12 . References:

Linux Partitioning Recommendations | Average Linux User

Linux Disk Partitioning Schemes - Land of Linux

C.3. Recommended Partitioning Scheme - Debian