Tuesday, January 28, 2014

Running DHCP Server on Slackware 14

Running DHCP server on Slackware 14 is quite trivial. Just run pkgtool from the command line and enable the dnsmasq service. Dnsmasq is in the services to start on start-up category. What is not very clear is the configuration file for this service. You will find /etc/dhcpd.conf file in Slackware but this is not the configuration file used by dnsmasq. Dnsmasq uses /etc/dnsmasq.conf as configuration file. You only need to uncomment one line in this file to enable the DHCP server, i.e. the line that contains dhcp-range option, for example:


The configuration above assumes the DHCP client are given address between the two IP addresses shown and a lease of 48 hours. If you have Windows computers running as client, you might want to uncomment this line too:
This tells Windows to release the DHCP lease when it shuts down. Well, now you can restart dnsmasq and see the result.

Tuesday, January 7, 2014

Preventing Trivial Malicious Access to Your Linux Server

One of the problem haunting Linux server installation on the internet is malicious accesses, such as port scanning. One of the lightweight option to run in your Linux server to provide protection against "trivial" malicious activity from the internet is the psad (http://cipherdyne.org/psad/). This solution uses iptables as the source for analysis.