How to create SWAP in Live Linux Server

How to create SWAP in Live Linux Server

[root@manage squid]# free -m

             total       used       free     shared    buffers     cached
Mem:          1005        712        292          0         23        231
-/+ buffers/cache:        457        547
Swap:          250         21        229

[root@manage squid]# df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda5             695M  373M  287M  57% /
/dev/sda1              23M  9.0M   13M  42% /boot
/dev/sda9             197M  928k  186M   0% /home
/dev/sda6             486M  156M  305M  34% /usr/local
/dev/sda7              32G   14G   16G  48% /var

[root@manage /]# dd if=/dev/zero of=/var/swapfile count=1024 bs=1024000

1024+0 records in
1024+0 records out

[root@manage /]# mkswap /var/swapfile

Setting up swapspace version 1, size = 1048571904 bytes

[root@manage /]# swapon /var/swapfile

[root@manage /]# free -m

             total       used       free     shared    buffers     cached
Mem:          1005        992         12          0         26        750
-/+ buffers/cache:        215        789
Swap:         1250         24       1226

[root@manage /]# vi /etc/fstab

/dev/sda5               /                       newfs   defaults        1 1
/dev/sda1               /boot                   newfs   defaults        1 2
/dev/sda9               /home                   newfs   defaults        1 2
/dev/fd0                /mnt/floppy             auto    noauto,owner    0 0
/dev/sda6               /usr/local              newfs   defaults        1 2
/dev/sda7               /var                    newfs   defaults        1 2
none                    /proc                   proc    defaults        0 0
none                    /dev/pts                devpts  gid=5,mode=620  0 0
/dev/sda8               swap                    swap    defaults        0 0
/var/swapfile           swap                    swap    defaults      0 0