Posts Tagged ‘bind’

Free eBook: Alternative DNS Servers

Friday, February 25th, 2011

Grab this 747 pages DNS eBook for Free; Written by Jan-Piet Mens, titled “Alternative DNS Servers”. I glance through at the eBook and found several interesting topics for DNS deployments.

  • Bind DLZ – The Bind extension which can store your data in database MySQL, PostgreSQL and etc.
  • NSD – A lot people didn’t know about Name Server Daemon, find out more from the eBook.
  • DNS Planning – Name Server deployment planning, capacity planning and how to scale.
  • PowerDNS – Configure and master it.
  • LDAP DNS – Deploy DNS server with LDAP.

Alright, enough with the talks, where to download the eBook? It’s FREE for Download here

Bind Error: “max open files (3520) is smaller than max sockets (4096)”

Monday, June 28th, 2010

Just notice one of the DNS server has the error message


28-Jun-2010 16:28:24.283 general: max open files (3520) is smaller than max sockets (4096)

It’s something to do with kernel setting, on FreeBSD, configure the following


shell> sysctl kern.maxfiles=4096
shell> sysctl kern.maxfilesperproc=4096

Alternatively, put the above configuration on /etc/sysctl.conf in order to configure it at start up level.

Turn on DNS Query Log on Bind

Wednesday, May 12th, 2010

You are running a recursive DNS server and would like to find out the statistic of your user browser behavior (Whether they browse Facebook or Google?). Turn on DNS query logs will allow you to find out the statistic. To turn on DNS query log in Bind, configure lines below on named.conf


logging{
        channel query_logging {
                file "/var/log/query.log" versions 3 size 10m;
                severity debug 3;
                print-time yes;
                print-severity yes;
                print-category yes;
        };

        category queries {
                query_logging;
        };
};

To turn on query logging while DNS service is running; you need to to rndc querylog and check the status with rndc status


shell> rndc querylog
shell> rndc status
version: 9.x.x
number of zones: 1200
debug level: 3
xfers running: 0
xfers deferred: 0
soa queries in progress: 0
query logging is ON
recursive clients: 0/0/1000
tcp clients: 0/100
server is up and running

query logging is ON indicates that DNS query logging is activated.