July 10, 2015

Hướng dẫn xóa phân vùng swap trên CentOS 6

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.

5.3.1. Reducing Swap on an LVM2 Logical Volume

To reduce an LVM2 swap logical volume (assuming /dev/VolGroup00/LogVol01 is the volume you want to extend):
  1. Disable swapping for the associated logical volume:
    # swapoff -v /dev/VolGroup00/LogVol01
    
  2. Reduce the LVM2 logical volume by 512 MB:
    # lvm lvreduce /dev/VolGroup00/LogVol01 -L -512M
    
  3. Format the new swap space:
    # mkswap /dev/VolGroup00/LogVol01
    
  4. Enable the extended logical volume:
    # swapon -va
    
  5. Test that the logical volume has been reduced properly:
    # cat /proc/swaps # free
    

5.3.2. Removing an LVM2 Logical Volume for Swap

The swap logical volume cannot be in use (no system locks or processes on the volume). The easiest way to achieve this it to boot your system in rescue mode. Refer to for instructions on booting into rescue mode. When prompted to mount the file system, select Skip.
To remove a swap volume group (assuming /dev/VolGroup00/LogVol02 is the swap volume you want to remove):
  1. Disable swapping for the associated logical volume:
    # swapoff -v /dev/VolGroup00/LogVol02
    
  2. Remove the LVM2 logical volume of size 512 MB:
    # lvm lvremove /dev/VolGroup00/LogVol02
    
  3. Remove the following entry from the /etc/fstab file:
    /dev/VolGroup00/LogVol02   swap     swap    defaults     0 0
    
  4. Test that the logical volume has been extended properly:
    # cat /proc/swaps # free
    

5.3.3. Removing a Swap File

To remove a swap file:
  1. At a shell prompt as root, execute the following command to disable the swap file (where /swapfileis the swap file):
    # swapoff -v /swapfile
    
  2. Remove its entry from the /etc/fstab file.
  3. Remove the actual file:
    # rm /swapfile

Related Posts:

  • Tối ưu server bằng Module Page Speed trên CentOS Nhân đọc bài này của Nguyên Nghĩa về cách cài đặt Module Page Speed để tối ưu máy chủ và từ đó tăng tốc độ tải của trang web dùng WHM/CPANEL, mình có nhã hứng muốn thử, ngặt cái là mình “con nhà nghèo”, không … Read More
  • HOW TO UPGRADE PHP 5.3.X TO 5.4.X OR 5.5.X ON CENTOS This tutorial was performed on CentOS 6.5 x86 (32-bit) vps. Step 1 – Login to your server via Command Line (Putty or Terminal) Step 2 – Add EPEL and Remi repositories onto your system: On CentOS 6.x 32-bit wget … Read More
  • Hướng dẫn cài đặt LAMP V2 trên Centos 6 LAMP V2 là gì ? Trước tiên để biết LAMP là gì các bạn có thể xem tut cài LAMP của mình tại đây:  Cài đặt LAMP trên VPS Centos Vậy LAMP V2 là gì ? Nó có gì khác so với LAMP ở tut trước ?  LAMP V2 thực tế vẫn là L… Read More
  • Cannot retrieve metalink for repository: epel on centos 6 I've got a VM running CentOS 6 (64bit) and I'm attempting to add the EPEL repo like usual to install various packages as I do quite regularly. Today, I'm experiencing some strange errors yet I'm doing absolutely nothing dif… Read More
  • How to backup a full Centos Server? Method 1: The best tool to use for this is probably dump, which is a standard linux tool and will give you the whole filesystem. I would do something like this: /sbin/dump -0uan -f - / | gzip -2 | ssh -c blowfish user@back… Read More

0 comments:

Post a Comment