Use OpenDNS for Free Content Filtering | If you have little kids at home, or need to setup content filtering for schools, OpenDNS is free and works great. I’ll show you how it works! First, change the DNS servers in your router to 208.67.222.222 and 208.67.220.220. Next, go to opendns.com and create a free account. Once inside your account, you will need
How to install host, nslookup and other BIND tools on Windows
How to install host, nslookup and other BIND tools on Windows | For a Linux admin using Windows, cygwin unfortunately does not provide host, nslookup, or other bind tools. I’ll show you how to download these BIND tools directly from ISC and have them work in your cygwin terminal! Note: this assumes you already have a working cygwin install. First, download the latest version of BIND for
Tunnel DNS through ssh -D socks proxy
Tunnel DNS through ssh -D socks proxy | When using ssh -D to setup a socks proxy, DNS queries and DNS traffic are not sent through the ssh tunnel. However, with Firefox a config change can be made to send DNS traffic through the ssh tunnel. Here’s how it works! First, establish an ssh proxy: $ ssh -D 9000 user@host Then in Firefox,
Use nmap to check DNS configuration best practices
Use nmap to check DNS configuration best practices | A new NSE script in nmap 6.25 checks DNS zone configuration best practices. I’ll show you how it works! First, you will need nmap 6.25 (or later) installed: http://nmap.org/download.html Now with nmap 6.25 installed, run the below command against a DNS server. In this example, I am checking the configuration of the zone google.com from
How to Fetch DKIM Records from DNS
How to Fetch DKIM Records from DNS | DKIM is simply a TXT record in DNS. A simple host command can fetch this record. I’ll show you how! The command is: $ host -t TXT dkimrecord So how do you find that dkim value? DKIM records are in the following format: [selector]._domainkey.[domain] The selector and domain are provided in the email headers of
Install BIND in Red Hat 6 or CentOS 6
Install BIND in Red Hat 6 or CentOS 6 | As of Red Hat 6 and CentOS 6, the DNS server bind is super easy to get up and running. Here’s how it works! Install bind: $ sudo yum install bind Start bind – the service is called named $ sudo /etc/init.d/named start Generating /etc/rndc.key: [ OK ] Starting named: [ OK ] Done. If
How to Grab | Disable BIND Version Banner
How to Grab | Disable BIND Version Banner | The BIND DNS server by default will broadcast its version publicly. Security-minded admins may want to disable broadcasting of the BIND banner. I’ll show you how! Grab BIND banner It is possible to use dig, host, nslookup or whatever your favorite DNS tool may be to query the BIND banner. I like the host command
Perform DNS Lookups with the host command
Perform DNS Lookups with the host command | The dig command is commonly used to make DNS queries. However, a much overlooked command is the host command. Here are some quick tips for a useful tool to add to your bag of tricks or to impress your friends. The syntax is: $ host [domain.com] When run with no options, a simple quick summary
Public IPv6 DNS Servers
Public IPv6 DNS Servers | While your local ISP may not yet have IPv6 DNS servers available, there are several free alternatives for use right now. OpenDNS – IPv6 2620:0:ccc::2 2620:0:ccd::2 he.net $ host ordns.he.net ordns.he.net has address 74.82.42.42 ordns.he.net has IPv6 address 2001:470:20::2 Google’s Public DNS: $ host google-public-dns-a.google.com. google-public-dns-a.google.com has address 8.8.8.8 google-public-dns-a.google.com has IPv6 address 2001:4860:4860::8888 See
DNS How-To for Google Apps Users
DNS How-To for Google Apps Users | Google Apps of course is awesome email, docs, calender and such for organizations or individuals. To further take advantage of Google Apps for your organization, it is possible to input additional DNS records. In doing this, mail.yourdomain.com goes to your google apps mail, as well as others: calendar.yourdomain.com – your google apps calendar docs.yourdomain.com
