使用LVM的方式扩展swap

对新磁盘进行分区并划分成 8e Linux LVM类型，在此不赘述，

1.vgextend扩展所在VG并创建LV

[root@xxxx ~]# vgextend rhel  /dev/sdc1
WARNING: swap signature detected on /dev/sdc1 at offset 4086. Wipe it? [y/n]: y
  Wiping swap signature on /dev/sdc1.
  Physical volume "/dev/sdc1" successfully created
  Volume group "rhel" successfully extended
  
  [root@xxxx ~]# lvcreate -n swap2 -L 16G rhel
  Logical volume "swap2" created.

2.mkswap将磁盘分区或文件设为Linux的交换区

[root@xxxx ~]# mkswap /dev/rhel/swap2
Setting up swapspace version 1, size = 16777212 KiB
no label, UUID=5473f362-f5e9-4946-8e3f-604c078f2289 

3.swapon命令激活Linux系统中交换空间：

swapon /dev/mapper/rhel-swap2

4.设置开机自启动

[root@xxxx ~]# vi /etc/fstab 
....
/dev/mapper/rhel-swap2   swap                    swap    defaults        0 0