Using a pre-authentication banner with ssh can verify identification before a password is entered. This can help prevent leaking passwords. Banners are simple to configure but often disabled in the default configuration.
Post related to Openwrt routers and their software
Providing IPv6 DNS resolver data with radvd
How to provide DNS server addresses to IPv6 clients using Router Announcements.
Implementing IPv6 Part 2
Replacing 6to4 tunnel with 6in4. IPv6 enabling Bind, Exim, SPF, Squid, and updating Databases containing IP addresses.
Transparent Squid Proxy
Over the holidays, I had a user experience and attempted browser hijacking. It appeared to have bypassed my squid proxy. My updated configuration now sends all web access via squid. The old firewall rules, that allowed direct access to the Internet, have been replaced with a transparent Squid proxy. This runs on my existing Squid Proxy using another port.
Implementing IPv6 6to4 on OpenWRT
As the IPv4 addresses begin to run out I finally invested the time to investigate and implement IPV6. As my ISP has not yet announced the availability of IPV6 addresses I chose to implement a 6to4 tunnel. This is simple to implement, and currently well supported. My external firewall is an ASUS wireless router running… Continue reading Implementing IPv6 6to4 on OpenWRT
Firewalling Google Chat and Skype
To enable for Internet chat I set up Google Chat and Skype. My firewall rules have been extremely restrictive with only known and approved services allowed to connect. Google Chat installed with no noticeable impact to the firewall. Things did not go so well with Skype. The installation of Skype resulted in lots of warnings… Continue reading Firewalling Google Chat and Skype
Monitoring with Munin
Munin is a system monitoring program designed to capture and graph performance statistics with minimal configuration. It is significantly easier to configure than MRTG and has a wide variety of plugins. The Ubuntu (Debian) installer will setup a reasonable configuration on installation. It requires one server, and a client daemon on all monitored servers including… Continue reading Monitoring with Munin
OpenWRT and Ubuntu dnmasq setup
Now I have replaced my old firewall with OpenWRT, I needed to enhance the configuration of dnsmasq to support the network. The old Ubunutu based firewall was already running dnsmasq, as does the DNS server on the LAN. I run a mixed network with wired and wireless clients on separate address ranges. DHCP services are… Continue reading OpenWRT and Ubuntu dnmasq setup
OpenWRT syslog-ng Installation
When I went to process my remote firewall log output from OpenWRT, I noticed that the entries were truncated. A quick check with tcpdump indicated that the syslog packets were truncated to 256 characters. As syslogd and klogd are both provided by BusyBox, I decided to replace them both. The obvious solution was to replace… Continue reading OpenWRT syslog-ng Installation