System information

# swapo n -v /d ev/Vo l G ro up0 0 /Lo gVo l 02
To test if the logical volume was successfully created, use cat /pro c/swaps or free to inspect the
swap space.
15.1.3. Creat ing a Swap File
To add a swap file:
Pro ced u re 15.2. Ad d a swap f ile
1. Determine the size of the new swap file in megabytes and multiply by 1024 to determine the
number of blocks. For example, the block size of a 64 MB swap file is 65536.
2. Type the following command with co unt being equal to the desired block size:
# d d i f= /d ev/zero o f= /swapfi l e bs= 10 24 co unt= 6 5536
3. Setup the swap file with the command:
# mkswap /swapfi l e
4. It is recommended that the permissions are changed to prevent the swap being world
readable.
# chmo d 0 6 0 0 /swapfi le
5. To enable the swap file immediately but not automatically at boot time:
# swapo n /swapfi l e
6. To enable it at boot time, edit /etc/fstab to include the following entry:
/swapfi l e swap swap d efaul ts 0 0
The next time the system boots, it enables the new swap file.
To test if the new swap file was successfully created, use cat /pro c/swaps or free to inspect the
swap space.
15.2. Removing Swap Space
Sometimes it can be prudent to reduce swap space after installation. For example, say you
downgraded the amount of RAM in your system from 1 GB to 512 MB, but there is 2 GB of swap
space still assigned. It might be advantageous to reduce the amount of swap space to 1 GB, since
the larger 2 GB could be wasting disk space.
You have three options: remove an entire LVM2 logical volume used for swap, remove a swap file, or
reduce swap space on an existing LVM2 logical volume.
15.2.1. Reducing Swap on an LVM2 Logical Volume
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