3- Design Hard Disk layout Flashcards
What is the only directory that cannot have a mount point of it’s own? what does it have to be under?
/etc, must be under ROOT mount point
/opt mount point
Third party application. optimize on its own drive
/var mount pont
used for mysql, where its data files (log, run and library files) located in /var
/boot mount boint
contain boot loader and kernel files (init ram), recommended 2 GiB size
swap
At least the size of your RAM + 50%.
/home
the size depends on the application and does not has a rule. for instance if it is a development server and gonna be used for multiple users
Standard partiton
to partition physical/logical device into one or multiple partitions. Its limitation is if one of the partitions is filled up, we have to transfer the partition into a free space one
LVM
Logical Volume Manager
A set of tools for allocation disks, striping, mirroring and resizing logical volumes.
It allows you to work with one or more disk drives or partitions, in groups, that can be dynamically assigned to pools of storage to be used as filesystems on your system.
What are the components of LVM?
1- PV - Physical Volume:
- The starting point of storage in LVM
- corresponding to a disk or partition on the system (either local to the system like /dev/sda1 or storage area network block device)
2- VG - Volume Group:
- a combination of one or more PVs to create a pool of available storage
- made up of PEs (physical extants) that break the PVs into units that can be used in a VG
3- LV - Logical Volume
- this is the usable space that allocated from VGs
- we can create multiple LVs from as single VG
- can be resized (increased or decreased) as needed based on available space in VG pool
- if the VG run out of space, simply adds one or more PVs , add them to VG and then to LV
Advantages of LVM
Flexibility - adjust the size of a logical volume, up or down. Allocating additional physical volumes to a volume group when needed allows you to dynamically make more space available.
Snapshots - make ‘point in time’ backups of your LV. This can then be used for easy backups, restores, migrations, testing, etc - all without affecting the ‘live’ filesystem.