Thread: Create swap partition after install

I already have parititon contain data under lvm enviroment with centos 5.8

output of fdisk -l

Code:

    Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
    255 heads, 63 sectors/track, 121601 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    
       Device Boot      Start         End      Blocks   Id  System
    /dev/sda1   *           1          25      200781   83  Linux
    /dev/sda2              26      121601   976559220   8e  Linux LVM

output of lvdisplay

Code:

   # lvdisplay
      --- Logical volume ---
      LV Name                /dev/sysvg/ROOT
      VG Name                sysvg
      LV UUID                6oy3Rj-ka3K-mL9s-vjjG-1Iqw-dniq-UbWzvJ
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                919.44 GB
      Current LE             29422
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:0
    
      --- Logical volume ---
      LV Name                /dev/sysvg/TMP
      VG Name                sysvg
      LV UUID                jTKLBt-eNz0-KxmV-E5Nk-jjC0-FlRb-qny62p
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                9.88 GB
      Current LE             316
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:1
    
      --- Logical volume ---
      LV Name                /dev/sysvg/SHM
      VG Name                sysvg
      LV UUID                NpKjhl-tzzn-Dk3G-A6dl-4QJB-QCc2-IkbDH5
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                2.00 GB
      Current LE             64
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:2

output of df -h

Code:

    root@server [~]# df -h
    Filesystem            Size  Used Avail Use% Mounted on
    /dev/mapper/sysvg-ROOT
                          891G  125G  721G  15% /
    /dev/mapper/sysvg-TMP
                          9.6G  153M  9.0G   2% /tmp
    /dev/mapper/sysvg-SHM
                          8.0G  8.0K  8.0G   1% /dev/shm
    /dev/sda1             190M   19M  162M  11% /boot
    tmpfs                 8.0G  8.0K  8.0G   1% /dev/shm

output for /etc/fstab

Code:

    root@server [~]# cat /etc/fstab
    /dev/sysvg/ROOT /       ext3    usrjquota=quota.user,jqfmt=vfsv0        1       1
    /dev/sysvg/TMP          /tmp                    ext3    defaults        1 2
    /dev/sysvg/SHM  /dev/shm        ext3    defaults,usrquota       1       2
    LABEL=/boot             /boot                   ext3    defaults        1 2
    tmpfs                   /dev/shm                tmpfs   defaults        0 0
    devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
    sysfs                   /sys                    sysfs   defaults        0 0
    proc                    /proc                   proc    defaults        0 0
    /tmp             /var/tmp                    ext3    defaults,bind,noauto        0 0

I don't have any idea how to create swap partition , and i worried about creating cause any DATA LOSS

It is easy....if you wish to have 512Mb swap , then follow as below:

dd if=/dev/zero of=/myswap bs=1024 count=524288
mkswap /myswap
chown root:root /myswap
chmod 600 /myswap
swapon /myswap


now, append in /etc/fstab file for persistence.

/myswap swap swap defaults 0 0

Originally Posted by iLinux85

I already have parititon contain data under lvm enviroment with centos 5.8

output of fdisk -l

Code:

    Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
    255 heads, 63 sectors/track, 121601 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    
       Device Boot      Start         End      Blocks   Id  System
    /dev/sda1   *           1          25      200781   83  Linux
    /dev/sda2              26      121601   976559220   8e  Linux LVM

output of lvdisplay

Code:

   # lvdisplay
      --- Logical volume ---
      LV Name                /dev/sysvg/ROOT
      VG Name                sysvg
      LV UUID                6oy3Rj-ka3K-mL9s-vjjG-1Iqw-dniq-UbWzvJ
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                919.44 GB
      Current LE             29422
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:0
    
      --- Logical volume ---
      LV Name                /dev/sysvg/TMP
      VG Name                sysvg
      LV UUID                jTKLBt-eNz0-KxmV-E5Nk-jjC0-FlRb-qny62p
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                9.88 GB
      Current LE             316
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:1
    
      --- Logical volume ---
      LV Name                /dev/sysvg/SHM
      VG Name                sysvg
      LV UUID                NpKjhl-tzzn-Dk3G-A6dl-4QJB-QCc2-IkbDH5
      LV Write Access        read/write
      LV Status              available
      # open                 1
      LV Size                2.00 GB
      Current LE             64
      Segments               1
      Allocation             inherit
      Read ahead sectors     auto
      - currently set to     256
      Block device           253:2

output of df -h

Code:

    root@server [~]# df -h
    Filesystem            Size  Used Avail Use% Mounted on
    /dev/mapper/sysvg-ROOT
                          891G  125G  721G  15% /
    /dev/mapper/sysvg-TMP
                          9.6G  153M  9.0G   2% /tmp
    /dev/mapper/sysvg-SHM
                          8.0G  8.0K  8.0G   1% /dev/shm
    /dev/sda1             190M   19M  162M  11% /boot
    tmpfs                 8.0G  8.0K  8.0G   1% /dev/shm

output for /etc/fstab

Code:

    root@server [~]# cat /etc/fstab
    /dev/sysvg/ROOT /       ext3    usrjquota=quota.user,jqfmt=vfsv0        1       1
    /dev/sysvg/TMP          /tmp                    ext3    defaults        1 2
    /dev/sysvg/SHM  /dev/shm        ext3    defaults,usrquota       1       2
    LABEL=/boot             /boot                   ext3    defaults        1 2
    tmpfs                   /dev/shm                tmpfs   defaults        0 0
    devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
    sysfs                   /sys                    sysfs   defaults        0 0
    proc                    /proc                   proc    defaults        0 0
    /tmp             /var/tmp                    ext3    defaults,bind,noauto        0 0

I don't have any idea how to create swap partition , and i worried about creating cause any DATA LOSS