Jan-Piet Mens.

I am a systems architect and consultant and sometimes available for hire. I am fluent in several programming languages and in four natural languages: English, Spanish, German and French. I'm proficient with all things Unix and Linux, and I'm particularly efficient when given the task of getting things to work for you.

I blog and tweet as @jpmens.

Areas of work

I play tricks with DNS and have authored Alternative DNS Servers, a 700 page book on Open Source DNS servers. I integrate Mail Transport Agents with LDAP directory services and make the two sing. I've done a lot of nitty-gritty with IBM/Lotus Domino (with the C API and a bit of Lotusscript) such as creating automatic user creation server-tasks. I'm very good at getting data in and out of systems, and I've built Public Key Infrastructure (PKI) systems with OpenSSL as well as setting up large Bacula backup installations.

I have successfully completed a large number of interesting projects; have a look at my profile.

Publications

In the course of the last years I've written large amounts of text, but most of it was for my clients and has probably long been recycled or is otherwise unretrievable from old punch cards, magnetic tapes or any other data carrier. Of the public documents, this lists some of the notable exceptions:

Conferences

I've recently held the following talks at conferences:

Exim and LDAP -- Making Exim talk to an LDAP directory server

The Exim Mail Transfer Agent contains support for querying information from LDAP directory servers. After a short refresher on LDAP and Exim's configuration, this talk will show you real-world examples of how to route e-mail depending on information gleaned from LDAP. We discuss virtual hosting, conditional routing, SMTP authentication, and adding your own attributes and object classes to configure Exim for particular tasks. We also show you how easy it is to add e-mail routing for your choice Groupware system. Held at the UKUUG Summer 2009 conference in Birmingham.

The Perdition and NGINX IMAP Proxies

The Perdition and nginx (Engine X) IMAP/POP-3 proxies enable clients to be directed to arbitrary back-end IMAP/POP-3 servers depending on the result of a database lookup. We discuss why you would want to implement such a proxy, what these tools can do for you, and show you how to configure the tools to suit a variety of situations. Held at the UKUUG Spring 2010 conference in Manchester.

A bird's-eye view on DNSSEC

It's inconceivable you don't know what DNS is, but do you know what DNSSEC is? As a UNIX/Linux admin you'd better. DNSSEC signs DNS replies and gives users a warm fuzzy feeling that all is well, but is it really? What is DNSSEC, and what problems does it solve? What is signing, which components are involved, what can go wrong? How do you detect that DNSSEC is working, and what can an experienced user do to prove it isn't? Held at the UKUUG Spring 2011 conference in Leeds, and at LOAD Days in April 2011.

Unbound as a caching validating DNSSEC resolver

You've heard of DNSSEC and want to install a validating DNSSEC caching server on your workstation to experience DNSSEC? We suggest you use Unbound -- a validating, recursive, and caching DNS resolver with some tricks up its sleeve.We'll show you how to configure Unbound to use it as a caching server on yourworkstation (yes, Windows also), ensure DNSSEC-validation is being performed, add DLV and tweak it to serve you some local DNS data. Held at the UKUUG Spring 2011 conference in Leeds, and at LOAD Days in April 2011.

DNSSEC zone-signing tool chest

DNSSEC key-management and zone-signing can be, but must not be, a pain. In forty-five minutes we give you an overview of utilities you can use to create keys and sign zones. Whether you prefer seeing rather than believing or want everything to be as automatic as possible, one of these tools will satisfy your signing needs. We'll discuss BIND's utilities, BIND's auto-signing, DNSSEC-tools, Zone Key Tool (ZKT), OpenDNSSEC, and PowerDNSSEC. Held at the UKUUG Spring 2011 conference in Leeds.

Contact

If you see me at a conference, I'd be glad if you talked to me. Otherwise, use e-mail. I prefer e-mail, but you can chat to me or phone.

Impressum

Inhaltlich Verantwortlicher gemaess § 10 Absatz 3 MDStV: Jan-Piet Mens, Walther-Rathenau-Str. 36, 33602 Bielefeld, 0171 8033011.

Haftungshinweis: Trotz sorgfaeltiger inhaltlicher Kontrolle uebernehmen wir keine Haftung fuer die Inhalte externer Links. Fuer den Inhalt der verlinkten Seiten sind ausschliesslich deren Betreiber verantwortlich.

Legal notices & Privacy policy

Responsible party in terms of the German TDG and data controller in terms of the GDPR:

Jan-Piet Mens
Walther-Rathenau-Str. 36
D-33602 Bielefeld
jp@mens.de
+491718033011

This Web site was designed with privacy in mind.

• upon accessing these Web pages, your Web browser transmits certain data (type of Browser, IP address, possibly referer information) to the server serving theses pages. Certain portions of this data is automatically logged by the server software in order to ensure the site can be operated. In particular the IP address is anonymized. The logs are destroyed after four weeks.
• the site does not set cookies.
• no external resources (fonts, CSS, etc.) are loaded
• these pages do not set tracking information nor does the site do analytics of any kind
• no personal data is collected, processed, or stored on this site.

This site contains links to websites of third parties ("external links"). As the content of these Web sites is not under my control, I cannot assume any liability for such external content. Operators of linked websites shall always be liable for their content and accuracy of the information provided. No illegal contents was recognizable at the time I placed the links.