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



























    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

























      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














      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












      share










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      asked 1 min ago









      TimTim

      27.2k78263472




      27.2k78263472






















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