jmenbo/disable_ipv6_centos_6.6.md

## disable_ipv6_centos_6.6.md

      
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              disable_ipv6_centos_6.6.md
            
          
    Disable IPv6 in CentOS 6.x

1) Add the file:

/etc/modprobe.d/ipv6.conf
With the following contents:
# Disabling ipv6
options ipv6 disable=1
2) Add the following lines to /etc/sysctl.conf:

# Disable IPv6
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
3) For systems with multiple NICs on different subnets:

On /etc/sysctl.conf change the following:
net.ipv4.conf.default.rp_filter = 1
To this:
net.ipv4.conf.default.rp_filter = 2
This change is needed due to a routing "bug" on CentOS 6.x.
See [here] (http://z-issue.com/wp/linux-rhel-6-centos-6-two-nics-in-the-same-subnet-but-secondary-doesnt-ping/) for partial explanation