Zone transfer setup for BIND with split horizon on the same zone

With the default configuration, a zone transfer from a master to a slave of BIND with split horizon has the slave transfer only the view of that zone that is available to its IP address. The documentation is a bit vague on the subject, but it turns out it is possible for the slave to transfer the zone definitions corresponding to all (or a subset) of the views. The idea is to identify the slave for zone transfer purposes using something else that its IP address.

How to transfer Duo Security installation to a new phone on Android

The Duo Security application can be used to generate one time passwords for online services, as an alternative to Google Authenticator. However, it does not offer a way to backup the configuration, so if for some reason it becomes unusable (say if your phone is stolen or broken) you will have to reinitialise all the accounts. There is however a way to get to this informaiton. It requires however the phone to be “rooted”.

Establishing IPSec tunnel between Linux and Fortigate

Here is an example of a tunnel setup beetween Linux and Fortigate. It uses StrongSwan. 1 2 3 4 5 6 7 8 9 10 11 12 13 conn myconn type=tunnel left=[local_ip_address] leftsubnet=[local_subnet_to_be_accessed_through_tunnel] right=[remote_ip_address] rightsubnet=[remote_subnet_to_be_accessed_through_tunnel] keyexchange=ike ikelifetime=28800s ike=aes256-sha1-modp1536 authby=secret keylife=1800s esp=aes256-sha1 auto=start This configures the forwarding policy. If you want to access the remote end of the tunnel from the gateway, set up a virtual interface and configure it with an address within the local_subnet.

IPv6 prefix delegation with static address and dhclient on Ubuntu / Debian

Some hosting providers, like Online in France provide IPv6 access via prefix delegation. You get a DUID that has to be sent to their DHCP server. The IP address is configured by the client. The recommended method is using Dibbler, but this solution is pretty buggy. On Ubuntu or Debian, you can use the provided dhclient to obtain the prefix delegation. Below are samples of dhclient6.conf and interfaces. Note that in this configuration everything is configured by the client, but you could request a name server from the DHCP server.

IPv6 routing and router advertisments on Ubuntu / Debian

If your Linux box gets its IPv6 routing information via router advertisments, you may have noticed that upon enabling forwarding, it disregards those advertisments and it loses the configured gateways. The have this configuration working again, set accept_ra 2 in /etc/network/interfaces. This value is not documented in the interfaces manual, but since kernel version 2.6.37 it allows the interface to both do forwarding and accept router advertisments. Source