添加一个swap分区
要求:
swap 分区容量为 512 MiB
当您的系统启动时，swap 分区应该可以自动挂载
不要移除或者修改其他已经存在于您的系统中的 swap 分区
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1、先查看一下目前系统中使用的swap分区，我的是只有一个，现在我要再添加个,容量是512M的
[root@desktop ~]# swapon -s
Filename Type Size Used Priority
/dev/sda2 partition 2047996 0 -1
2、用分区工具重新划分一个容量为512M的分区，逻辑分区主分区都可以，推荐使用逻辑分区
[root@desktop ~]# fdisk /dev/sda
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): p 看一下目前的分区状态
Disk /dev/sda: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000bffad
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 20482047 10240000 83 Linux
/dev/sda2 20482048 24578047 2048000 82 Linux swap / Solaris
/dev/sda3 24578048 25602047 512000 83 Linux
Command (m for help): n 使用n新建分区
Partition type:
p primary (3 primary, 0 extended, 1 free)
e extended
Select (default e): e 选择拓展分区
Selected partition 4
First sector (25602048-41943039, default 25602048):
Using default value 25602048
Last sector, +sectors or +size{K,M,G} (25602048-41943039, default 41943039): --->我这里就把剩余的空间全给这个扩展分区了
Using default value 41943039
Partition 4 of type Extended and of size 7.8 GiB is set
Command (m for help): n 按n继续分区，开始分逻辑分区
All primary partitions are in use
Adding logical partition 5
First sector (25604096-41943039, default 25604096):
Using default value 25604096
Last sector, +sectors or +size{K,M,G} (25604096-41943039, default 41943039): +512M 输入我要分区的大小
Partition 5 of type Linux and of size 512 MiB is set
Command (m for help): t 按t修改分区类型
Partition number (1-5, default 5):
Hex code (type L to list all codes): 82 修改为swap类型
Changed type of partition 'Linux' to 'Linux swap / Solaris'
Command (m for help): w 按w保存退出
[root@desktop ~]#partprobe 刷新磁盘信息
3、格式化分区为swap格式，并且启用
[root@desktop ~]# mkswap /dev/sda5 格式化
Setting up swapspace version 1, size = 524284 KiB
no label, UUID=8a529678-5180-4c8c-bd2c-18677c573ba3
[root@desktop ~]# swapon /dev/sda5 启用
[root@desktop ~]# swapon -s 查看正在使用的swap分区，已存在
Filename Type Size Used Priority
/dev/sda2 partition 2047996 0 -1
/dev/sda5 partition 524284 0 -2
4、配置开机自动挂载
[root@desktop ~]# blkid 看要挂载的swap分区的UUID，然后复制
/dev/sda1: UUID="3c6e20fa-3e12-42ca-8dba-b12eee74e43e" TYPE="xfs"
/dev/sda2: UUID="ff7d2e6d-c2d7-46a0-af09-70c85898ab46" TYPE="swap"
/dev/sda3: UUID="4Ntfep-th0e-bCXr-Qo3b-EPJ1-SRsu-nfeOru" TYPE="LVM2_member"
/dev/sda5: UUID="8a529678-5180-4c8c-bd2c-18677c573ba3" TYPE="swap"
/dev/mapper/vg0-lv0: UUID="b2285e5e-de78-4392-945a-817843fd7f10" TYPE="ext3"
[root@desktop ~]# vim /etc/fstab 编辑挂载文件，内容如下图
[root@desktop ~]# mount -a 重新加载挂载表
[root@desktop ~]#
