Linux   Linux – rsyslog: parsing and splitting message fields



Until now I hadn’t used the options and features rsyslog comes with. Let me show a simple example I have done today. This is an example log line rsyslog has received from iptables (I have configured iptables to log certain connections attempts to identify and save devices with malware):

Sep 29 15:30:39 myserver kernel: [malware3] IN=ens192 OUT=ens192 MAC=XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX SRC=10.15.13.17 
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Linux   Linux – Simple DNS server using DNSmasq



This article offers a 5 min howto about configuring your own DNS server (perhaps for your company or maybe for your home network) using DNSmasq. Obviously, only the surface is covered on this post.

Given my router does not allow me to add host entries for local DNS resolution, I decided to use DNSMasq on one of my internal network … Read more

Linux   Linux – Exim: Authenticated and TLS mail through smarthost



Exim is a very flexible and common MTA (mail transfer agent) in Unix systems.
This posts shows the way to configure Exim as client to send authenticated and encrypted (TLS) emails through a smarthost.

Lets suppose the smarthost email server is listening on port 587 for secure outgoing SMTP…

Configure exim to use the smarthost

To configure exim In … Read more

Linux   Linux – TCP listener daemon with tcpserver



To configure passive checks in Nagios/icinga I use a tcp listener daemon that launches a script (See Nagios – Using passive checks without agent)
Tried to use inetd superserver daemon, but in the last versions, i have not been able to make it work correctly (See last update in my post: Linux – cannot found / missing inetd.conf)Read more

Linux   Linux – cannot found / missing inetd.conf



Trying to configure a new inetd service needed for my Icinga (see Linux – Create custom inetd service), but i have not been able to find the inetd.conf file.
It seems inetd is not installed by default in the last Debian versions (mine is 9 – stretch).

Luckily, it is packetized in the inetutils-inetd

# apt-get install inetutils-inetd
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Icinga icon   Icinga – Installation / Setup on Debian Linux (1)



As you can see in previous posts…, Im in love with Nagios to monitor my systems… after creating some powerful, customized plugins for my Checkpoint firewalls, Exchange servers… cannot live with it… but maybe, it's "a bit" old fashioned and I have decided to try the Icinga monitoring tool. If it fits my environment, I'll have to replace my old … Read more