How to extend Swap space in Logical Volume

1.     Find out the name of the swap logical volume using the "lvs" command

[root@hostname ~]# lvs

  LV          VG             Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert

  lv_download vg_hostname -wi-ao---- 200.00g

  lv_holding  vg_hostname -wi-ao---- 200.00g

  lv_home     vg_hostname -wi-ao----   4.88g

  lv_opt      vg_hostname -wi-ao----  29.49g

  lv_root     vg_hostname -wi-ao----   5.08g

  lv_swap     vg_hostname -wi-ao----   4.00g

  lv_tmp      vg_hostname -wi-ao----   4.98g

  lv_usr      vg_hostname -wi-ao----   4.98g

  lv_var      vg_hostname -wi-ao----   9.96g


2.     Find out LV path for swap logical volume

[root@hostname ~]# lvdisplay

--- Logical volume ---

  LV Path                /dev/vg_hostname/lv_swap

  LV Name                lv_swap

  VG Name                vg_hostname

  LV UUID                IhGUco-xoJp-zQ6S-o8iw-ivdc-fHWE-XS3zI2

  LV Write Access        read/write

  LV Creation host, time, 2015-06-05 10:37:23 +0200

  LV Status              available

  # open                 1

  LV Size                4.00 GiB

  Current LE             1024

  Segments               1

  Allocation             inherit

  Read ahead sectors     auto

  - currently set to     256

  Block device           253:1


3.     Turn off the swap partition

[root@hostname ~]# swapoff /dev/vg_hostname/lv_swap

4.     Resize the swap partition, adding 12GB more space to it

[root@hostname ~]# lvresize -L+12G /dev/vg_hostname/lv_swap

  Size of logical volume vg_hostname/lv_swap changed from 4.00 GiB (1024 extents) to 16.00 GiB (4096 extents).

  Logical volume lv_swap successfully resized


5.     Format the new swap space to make it usable

[root@hostname ~]# mkswap /dev/vg_hostname/lv_swap

mkswap: /dev/vg_hostname/lv_swap: warning: don't erase bootbits sectors

        on whole disk. Use -f to force.

Setting up swapspace version 1, size = 16777212 KiB

no label, UUID=b6195773-eba1-4af7-aafc-466867757985

Turn the swap volume back on:

[root@hostname ~]# swapon /dev/vg_hostname/lv_swap

6.     Check swap space

[root@hostname ~]# free -tom| grep -i swap

Swap:        16383          0      16383