Why do we need both mkswap and /etc/fstab to set up swap?












0















Given



$ cat /etc/fstab
...
/dev/mapper/lubuntu--vg-swap none swap sw 0 0


why do we still need:



$ sudo swapoff /dev/mapper/lubuntu--vg-swap
$ sudo mkswap /dev/mapper/lubuntu--vg-swap
$ sudo swapon /dev/mapper/lubuntu--vg-swap


?



In other wors, why do we need both mkswap and /etc/fstab to set up swap? What do mkswap and /etc/fstab do differently?



My question comes from https://unix.stackexchange.com/a/502591/674



Thanks.










share|improve this question























  • mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

    – jordanm
    3 mins ago
















0















Given



$ cat /etc/fstab
...
/dev/mapper/lubuntu--vg-swap none swap sw 0 0


why do we still need:



$ sudo swapoff /dev/mapper/lubuntu--vg-swap
$ sudo mkswap /dev/mapper/lubuntu--vg-swap
$ sudo swapon /dev/mapper/lubuntu--vg-swap


?



In other wors, why do we need both mkswap and /etc/fstab to set up swap? What do mkswap and /etc/fstab do differently?



My question comes from https://unix.stackexchange.com/a/502591/674



Thanks.










share|improve this question























  • mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

    – jordanm
    3 mins ago














0












0








0








Given



$ cat /etc/fstab
...
/dev/mapper/lubuntu--vg-swap none swap sw 0 0


why do we still need:



$ sudo swapoff /dev/mapper/lubuntu--vg-swap
$ sudo mkswap /dev/mapper/lubuntu--vg-swap
$ sudo swapon /dev/mapper/lubuntu--vg-swap


?



In other wors, why do we need both mkswap and /etc/fstab to set up swap? What do mkswap and /etc/fstab do differently?



My question comes from https://unix.stackexchange.com/a/502591/674



Thanks.










share|improve this question














Given



$ cat /etc/fstab
...
/dev/mapper/lubuntu--vg-swap none swap sw 0 0


why do we still need:



$ sudo swapoff /dev/mapper/lubuntu--vg-swap
$ sudo mkswap /dev/mapper/lubuntu--vg-swap
$ sudo swapon /dev/mapper/lubuntu--vg-swap


?



In other wors, why do we need both mkswap and /etc/fstab to set up swap? What do mkswap and /etc/fstab do differently?



My question comes from https://unix.stackexchange.com/a/502591/674



Thanks.







linux fstab swap






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 15 mins ago









TimTim

27.2k78263472




27.2k78263472













  • mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

    – jordanm
    3 mins ago



















  • mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

    – jordanm
    3 mins ago

















mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

– jordanm
3 mins ago





mkswap sets up the swap space. fstab just saws to use the swap space (eliminating the need to manually use swapon on boot).

– jordanm
3 mins ago










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