Dynamic DNS

If you host your own domain name server and if you want to securely and dynamically update some DNS entries, here is a small howto.

Here is in a nutshell what we are going to do:

1. Create a secret key to securely update the DNS zone
2. Configure a dynamic (sub) zone in your DNS server
3. Create a script to update a DNS entry

[Read more]

SNMP on Debian

If you want to monitor your servers from a central management station, you’ll probably need to configure an SNMP daemon on your servers. Here is a quick note to show you how easy it is to get started with SNMP on Linux machine (examples are for Debian but should be easy to adapt for other distribution). [Read more]

Dual stack IPv4/IPv6 on FreeBSD

Here is a quick note to show how easy it is to enable a dual IP stack on FreeBSD (and actually on most modern system)… [Read more]

ACE software upgrade

Cisco Application Control Engine Module (ACE) load-balancers are designed to work in standalone mode or in cluster mode. When running in standalone mode, software upgrade has obviously a great impact on the traffic going through the load-balancer. All the sessions will be dropped and no new session will be accepted until the ACE restarts with the new image (up to 8 minutes). [Read more]

VPS for rent

You need a server connected to Internet? You don’t want a shared server but you don’t want to pay for a dedicated server? exp-NETWORKS can rent you a Virtual Private Server (VPS). A VPS runs its own Linux OS with its own packages, users administration, configuration on a shared hardware. The VPS running on the same hardware are isolated from each other. [Read more]

ClamXav differential update

ClamXav is a free virus checker for Mac OS X. It uses the tried, tested and very popular ClamAV open source antivirus engine as a back end.

The default install of ClamXav does not enable the automatic virus definition update. When a user enables those automatic updates, a ‘good old cron job’ is created for that user. Three minor concerns [Read more]