Solving Slowness Accessing Via VPS

SLOW access via an IPV6 from a VPS in Australia? Here is the solution to solve slowness accessing through your VPS.

Due to the way most operating systems work, IPv6 is preferred before IPv4 when available - however the world isn't fully IPv6 ready even though many sites are supporting it - eg google has IPv6 - but It's not in Australia - so it's SLOW accessing it via an IPV6 from a VPS in Australia (and we wouldn't be surprised if the IPv6 international trunks are substantially smaller than IPv4).

You can use this Microsoft support article to prefer v4 over v6 (it lays the blame at mis-configured routers - not the case here - It's just that we're ahead of most of the rest of the world) or you can disable IPv6 on hosts which don't need/want it.

For linux variants there is an article here on how to disable IPv6: http://activemq.apache.org/multicast-watch-out-for-ipv6-vs-ipv4-support-on-your-operating-system-or-distribution-or-network.html

Interestingly, the latency between Melbourne to Sydney over ipv6 is also high - something which VPSBlocks or our DC have no control over (yet).

Disabling in Windows 2008

Download the fix onto your VPS and install it: http://go.microsoft.com/?linkid=9728870

Disabling in Windows 2012

Right click on the powershell icon and choose 'Run as Administrator', then paste in this command:

New-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\services\TCPIP6\Parameters -Name DisabledComponents -PropertyType DWord -Value 0xffffffff

You may need to restart afterwards.

Disabling in CentOS 5.3

Disable IPV6 support on your Linux machine by adding a line at the end of /etc/modprobe.conf by doing the following:

• SSH into your VPS (we recommend using Putty)
• Type: pico /etc/modprobe.conf
• Go to the end of the file and enter this line:
• alias net-pf-10 off # disable IPV6
• Save the file and exit pico.
• Restart the VPS

Disabling in CentOS 5.4+

• Edit /etc/sysconfig/network and set "NETWORKING_IPV6" to "no"  
• For 5.4 and later, replace in /etc/modprobe.conf

   alias ipv6 off

with:

   options ipv6 disable=1
 

Disabling in CentOS 6 or 5.4+

Add the following to /etc/sysctl.conf:

net.ipv6.conf.all.disable_ipv6 = 1

Alternative Method where modprobe.d is installed

touch /etc/modprobe.d/disable-ipv6.conf

echo "install ipv6 /bin/true" >> /etc/modprobe.d/disable-ipv6.conf 

Run /sbin/chkconfig ip6tables off to disable the IPv6 firewall

Reboot the system

Disabling in Linux (Debian)

Append the following to /etc/gai.conf

precedence ::ffff:0:0/96  100