Disabling IPv6 support in Red Hat Enterprise Linux 7

Disable ipv6 built-in kernel module.

1. Edit /etc/default/grub and append ipv6.disable=1 to GRUB_CMDLINE_LINUX like the following sample:
   

   GRUB_CMDLINE_LINUX="rd.lvm.lv=rhel/swap 

     crashkernel=auto rd.lvm.lv=rhel/root ipv6.disable=1"
   

2. Run the grub2-mkconfig command to regenerate the grub.cfg file:
   

   # grub2-mkconfig -o /boot/grub2/grub.cfg
   

   Alternatively, on UEFI systems, run the following:
   

   # grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
   

3. Reboot the system to disable IPv6 support.