3-4 Add New Partitions and Logical Volumes and Swap to a System Non-Destructively

Question 1

free -m

Answer 1

shows available physical memory and available swap memory

Question 2

how is swap used

Answer 2

new processes start with physical memory

idle memory from older processes will be allocated over to swap

Question 3

For swap generally good to use 2x to 2.5x of physical memory ex: 1GB physical so assign 2G or 2.5GB to swap

Answer 3

Best practice to assign swap size as

Question 4

fdisk
option: n for setting up whole disk
enter for all defaults, will default set size to full disk
option: l (lowercase L) to see labels
option: t to give it label found from l option output list ex: 8e for linux lvm to make swap space
option: w to write changes to disk and exit

pvcreate /dev/xvda
pvdisplay
vgcreate newVolumeGroup1 /dev/xvda (to assign it to new volume group as its made)
vgdisplay

lvcreate -n newNamedLV_Swap (ex Swap) -L 2GB newVolumeGroup1

lvdisplay

Answer 4

How to make an LVM to use to make swap on

Question 5

format it with swap signature with mkswap command
mkswap /dev/newVolumeGroup1/newNamedLV_Swap
mkswap returns with UUID, which can be used to mount it in fstab

swapon /dev/newVolumeGroup1/newNamedLV_Swap
free -m
swapon does not make it persistent swap storage, it needs to be added to /etc/fstab (similar to mount)

to take off swap mount
swapoff /dev/newVolumeGroup1/newNamedLV_Swap

free -m

Answer 5

How to format LVM (partioned, vg, and lv made. Label added 8e Linux LVM) into swap

Mount it as swap,

check swap space and physical memory

Question 6

Swap in /etc/fstab
/dev/newVolumeGroup1/newNamedLV_Swap swap swap 0 0

Or

UUID=(UUID from mkswap command, and check blkid) swap swap 0 0

Answer 6

Set swap space mount as persistent

Question 7

swapon -a

Answer 7

mount all swap entries in /etc/fstab file

Question 8

fdisk to make mbr partition
fdisk /dev/xvda
option: n 
     size +2G
option: L to see labels, 82 for 'Linux swap / Solaris'
option: t to label, put 82
option: w to save and exit

to put swap signature on it
mkswap /dev/xvda
returns with UUID to use in /etc/fstab for persistence

swapon /dev/xvda
free -m

Answer 8

How to make disk into swap space

Question 9

swapoff -a

Answer 9

Unmounts all swap entries in /etc/fstab

Question 10

swapon -s

Or
cat /proc/swaps

Answer 10

two ways to check which partitions and files are make up swap