Saturday, May 26 2012

Installing ipset on CentOS 6

I assume this will work on RedHat 6 too:

# yum install

Yes, you can copy and paste.

Note that this isn't adding any repositories, so I'm not sure what impact this will have in future since the packages won't get automatically updated by `yum update` (security updates, breakage when kernel updates etc?)

Thursday, February 10 2011

Native IPv6 with Internode and CentOS

This is a WIP. Notes so far.

At the moment, this results in an error from DHCPv6 Client when trying to assign an addrss to ppp200:

Feb 10 23:28:50 tank dhcp6c[1063]: transmit failed: Network is unreachable

Manually adding an address makes it work:

Feb 10 23:28:47 tank dhcp6c[1382]: request prefix is 2001:44b8:7206:d180::/60
# ip -6 a a 2001:44b8:7206:d180::1/48 dev ppp200
# ping6 2001:44b8:1::6
PING 2001:44b8:1::6(2001:44b8:1::6) 56 data bytes
64 bytes from 2001:44b8:1::6: icmp_seq=0 ttl=59 time=27.8 ms
64 bytes from 2001:44b8:1::6: icmp_seq=1 ttl=59 time=27.3 ms
64 bytes from 2001:44b8:1::6: icmp_seq=2 ttl=59 time=27.6 ms

Continue reading...

Tuesday, October 19 2010

Custom Actions with fail2ban

Most people are familiar with the fail2ban package available for protecting against brute-force password attacks against your servers.

Fail2ban scans log files like /var/log/pwdfail or /var/log/apache/error_log and bans IP that makes too many password failures. It updates firewall rules to reject the IP address.

What you might not have experimented with is it's ability to execute custom actions instead (or as well as) blocking the source IP in iptables.

Continue reading...

Saturday, January 30 2010

Migrating Physical Machine to Virtual Machine

This a quick step-by-step for migrating a Physical computer to a Virtual Box instance. It was written for an Arch Linux based installation, and requires no special software except for an Arch Linux installation CD / ISO image.

Continue reading...

Monday, November 2 2009

Adding Swatch Internet Time to Gnome

How to add an applet to your Gnome panel displaying Swatch Internet Time

Continue reading...