First you need to stop cpanel, apache , mysql services:

/etc/init.d/cpanel stop
/etc/init.d/httpd stop
/etc/init.d/mysql stop

Here I am increasing the tmp disk space to 2GB

root@test [/var/tmp]# vim /scripts/securetmp
———————————->
my $tmpdsksize = 512000; # Must be larger than 250000

my $tmpdsksize = 2097152; # Must be larger than 250000
———————————->
root@test [/]# umount -l /tmp
root@test [/]# umount -l /var/tmp
root@test [/]# mv /usr/tmpDSK /usr/tmpDSK_back

Modify /scripts/securetmp to set tmpdsksize to desired size:

root@test [/var/tmp]# /scripts/securetmp
Would you like to secure /tmp & /var/tmp at boot time? (y/n) y
Would you like to secure /tmp & /var/tmp now? (y/n) y
Securing /tmp & /var/tmp
/tmp is already secure
/var/tmp is already secure
Checking fstab for entries …Done
Logrotate TMPDIR already configured
Process Complete

Start cpanel, apache , mysql services:

/etc/init.d/cpanel start
/etc/init.d/httpd start
/etc/init.d/mysql start
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