≡ Menu

Assigning /31 prefix address to interfaces

When it comes to subnetting most people usually stop at /30. This will give them a netmask of 255.255.255.252 thus resulting in two usable IP address along with one Network and one Broadcast address.

The /31 subnet prefixes was introduced in RFC3021 which defines that it can be used on a point-to-point link. A point-to-point interface does not need broadcast address, therefore we don’t really need to assign a /30 address prefix. On a /31 bit segment, both addresses are interpreted as hosts addresses.

The main advantage of using /32 prefix will enable us to limit the number of network address required on a segment. Therefore, if a company using multiple point-to-point networks using public IP addresses, then they will be able to save half of its allocated IP space.

[click to continue…]

This post will cover the IPv6 configuration on Ubiquiti Edge Router ERPoE-5 running Version 1.9.1. I will be going through the whole process of setting up IPv6 connectivity using Hurricane Electric 6in4 tunnel.

I will not be using the real IP Addresses, however the reader should be able to understand and substitute for their own configuration.

This is a home network, therefore a lot of aspects are not considered in the design!

Overview

  • There are three VLANs. (Main (1) , Guest (2) , Automation (3) )
  • Since there is no native IPv6 support from my ISP, I am using a 6in4 Tunnel to get IPv6 working.
  • The EdgeRouter is the public facing device connected to a vDSL Modem via eth0.
  • The Ethernet interfaces eth1, eth2, eth3, eth4 are bridged via bridge interface br0.
  • Bridge interface br0 has a 192.168.1.1/24 RFC1918 address assigned to VLAN1 and also used as the management IP.

Part 1

In this part, I will be covering the tunnel creation. You need to head to Hurricane Electric (HE) https://www.tunnelbroker.net and get yourself an IPv6 tunnel. I have used a /48 Routed Prefix for my configuration which you can see below.
[click to continue…]

Route Distinguisher vs Route Target

The Route Distinguisher (RD) and the Route Target (RT) can be somewhat confusing to someone who is trying to learn the concept on MPLS. In this post, I will try and explain what RD and RT are in relation to MPLS.

To answer this question, we will use the following diagram.

mpls

[click to continue…]

On Cisco ASA, You cannot have DHCPd and Relay configured at the same time.

  • You can either add a relay server and add the DHCP scopes.
  • You can add different DHCP scope to the ASA DHCPd.

Visco VIRL sometimes throw the following error stating KVM acceleration is not available on hosts running ESXi.

KVM acceleration is not available

INFO: Your CPU does not support KVM extensions
KVM acceleration can NOT be used

You can also run the kvm-ok command to find the status of KVM accleration.

This is due to a missing setting on ESXi Guest OS and the following parameter needs to be added VM’s .VMX configuration file.

Please make sure the VM is shut down before making the change.

vhv.enable = “TRUE”

You can also add this parameter to /etc/vmware/config of the host, but it is not imperative you should do it.

IANA ROOT DNS Object-Group

The following object-group consists the latest IANA ROOT DNS Servers which can be used on the Cisco ASA firewalls.

IANA Root DNS Servers (IPv4/IPv6)
object-group network IANA-ROOT-DNS
 description IANA Root DNS Servers (IPv4/IPv6)
 network-object host 198.41.0.4
 network-object host 2001:503:ba3e::2:30
 network-object host 192.228.79.201
 network-object host 2001:500:84::b
 network-object host 192.33.4.12
 network-object host 2001:500:2::c
 network-object host 199.7.91.13
 network-object host 2001:500:2d::d
 network-object host 192.203.230.10
 network-object host 192.5.5.241
 network-object host 2001:500:2f::f
 network-object host 192.112.36.4
 network-object host 128.63.2.53
 network-object host 2001:500:1::803f:235
 network-object host 192.36.148.17
 network-object host 2001:7fe::53
 network-object host 192.58.128.30
 network-object host 2001:503:c27::2:30
 network-object host 193.0.14.129
 network-object host 2001:7fd::1
 network-object host 199.7.83.42
 network-object host 2001:500:3::42
 network-object host 202.12.27.33
 network-object host 2001:dc3::35

[click to continue…]

Copyright © Nish Vamadevan 2002-2017. All Rights Reserved. Terms and Policies.