Welcome @ KvV-Consultancy:
KvV - Consultany is a small company consisting mainly of Kees van Veen with the help of additional freelancers when required. Based on what expertise is needed expertise can be acquired from colleagues we worked previously with or from other resources from within our personal network or even externally hired.
Expertise is roughly outlined in two different areas.
- System administration
- Software development
In general "Off the Shelf" solutions cover a great deal of the issues risen when administrating systems. However there are occasions when specific solutions are preferred.
This can start off with a simple shell / perl script or even a whole application depending on the requirements stated for a system or application. Preferably OpenSource software (or modules / objects) are chosen for solutions because of it's flexibility and availability.
In my case I like to differentiate between the above mentioned areas of expertise, coming from System Administration and developing specific software for
maintaining Systems is what I find the most interesting.
You can download my resume from the menu-item Resume.
KvV - Consultancy cooperates with freelance colleagues we worked with in the past or when expertise is not available in our own network expertise can be acquired through partners.
a brief overview of in-house expertise:
- Setup / maintaining / LCM / expanding / developing Linux / Windows / Mobile client server or web based solutions.
- Server / Storage / Hosting / Cloud / Virtualisation management.
- Database modeling / optimizing / performance tuning on different architectures.
- Interfacing through Web / Email / telephony / VOIP and or SMS services.
- Networking / Security / Encryption / VPN and or other forms of connectivity over different media.
- Development on Linux / Web / Windows / Mobile applications.
Above mentioned is just a glimpse from the extensive experience found in the resume from Kees van Veen.
Most of these areas of expertise are also personal interests.
The world is changing all the time and demanding new solutions / technologies for new problems. These days everyone is carrying a smartphone with accordingly demands.
Cloud storage / messaging / voip / security for mobile devices deserve these days more and more attention.
A logical step for me was to jump on Android since Android is powered by Linux. Next step when you have mobiles to maintain you also want to make sure you can offer
the connectivity equal to services like Google offers. However these should be delivered at a corporate level where data is protected and not published by Google or any other 3th party.
My Curriculum Vitae can be downloaded at this moment only in English, in PDF or Word 2013 (docx) format.
Smart- phones these days come mainly in two different flavors Apple and Android. Both Smart- phones have their own applications and ability to download more apps in a store. Of course a Smart- phone
would not be attractive if it does not provide everyday needed services like email / storage and or messaging etc.
In general these services can be obtained from the vendors and or other 3th parties. In case when you have nothing to loose and you run these services for private use you are probably
more then happy with these vendor offered services.
The services used within companies like email and or storage most of the times are offered through accepted / well known interfaces like Active Sync and or encrypted connections in order
to secure the transmission between the companies Intranet and or public Internet.
Connections in general can be secured with certificates and or encryption through tunnels by using the pre- installed software on the smartphone.
Software of interest at serverside for connections is:
- l2tp/ipsec / OpenVPN
- z-Push (open source Active Sync protocol implementation)
- an Email platform (like Zarafa) that supports Active Sync.
Zarafa (https://www.zarafa.com) is a very complete solution featuring most common needed / wanted features you can think of when you need a professional email solution similar to Exchange.
If you are looking for a scalable and professional solution which is low- cost I would recommend taking a look at it, and when budget allows it, sign up for a support contract to ensure your ongoing business.
Zarafa developed z-Push (Active Sync) for the integration with smartphones and released it as OpenSource. I have used Zarafa for some years and I was very happy with it until lightning struck which raised an issue with my Zarafa setup.
Z-Push is written in PHP and can handle several backends. Since this is Open Source software I choose a different mailer integration and used z-Push again to exchange the data with the Smart- phone.
This is a nice example of the flexibility of OpenSource Software.
Owncloud ( http://owncloud.org ) is another example of the flexibility of OpenSource software where the user is free to choose whether he/she wants a support contract or support the product with in- house expertise.
The product aims to be an alternative to Google Drive and uses known technologies to implement storage solutions. The product is written in PHP and can be hosted on any LAMP environment.
Owncloud can also interface through z-Push (Active Sync) service although it is called oczupsh.
Again a nice example of OpenSource software which is an alternative ready to be used in your company providing similar services but managed / controlled by your company alone.
Chrome will mark all HTTP sites as ‘not secure’ starting in July ( Google Security Blog ) .
So .. if you run a site with several different domainnames, you need to take action in order to avoid that ugly red message.
Getting a certificate per site might be a solution, however if you have several, or even lots you might consider a wildcard, like "*.color-domain.com".
Of course you can follow a traditional setup and purchase whatever you need, but tinkering an evening might deliver an alternative
and even more cheap solution. Try "certbot" ( https://certbot.eff.org ) an opensoure solution using "lets-encrypt" for getting free certificates.
Setup can be done from package management in auto or manual mode, really helpfull and cheap solution to get your http pages https enabled.
Roundcube is a very nice and complete Web-based Email client with a rich set of plug-ins available like: Contacts and a Calendar.
Unfortunately there is no native support for enabling the One in All solution over Active Sync.
Fortunately RoundCube is coded in PHP and z-Push is available, so 1 + 1 makes 2.. Alex Charret figured out the same thing and started with a backend implementation for RoundCube in z-Push.
I took the liberty to take this implementation 1 step further and integrated his solution into the already existing imap backend which delivers now Email & Contacts.
I reworked the code, it now supports Imap E-Mail (with attachment fixes) & Contacts & the Calendar, Notes are still not implemented.
If you are interested, you can download
and install the backend to enable imap mail & Contacts & Calendar on z-push-2.2.1-1939 (this is the latest version I tested it against) & Roundcube.
A word of advice: The easiest way to set this up, is to setup the original imap backend to ensure all is working.
Download the roundcube backend, configure it simular to the email backend and you should be fine.
Minimal requirements are: php (libawl-php on debian: "apt-get install libawl-php") + mysql + roundcube + calendar plugin.
Kees van Veen
Centralized Fail- Over Ip Arbiter ( CFoIa ):
CFoIa is a very simple approach to managing cluster nodes (active/active) without complicated stacks like combinations of HeartBeat / Corosync / Pacemaker / STONITH / DRDB
and or other various Cluster Management software, the only requirment is HeartBeat + php + mysql. It is an Linux HA Cluster OCF (Open Cluster Framework) script
which acts on any event coming from HeartBeat in order to update the status from the nodes in a cluster into a centralized place (i.e. mariaDb with Galera- / mysql Cluster - DB ).
Most clusters are build around a single virtual ip (LVS) and or load balancer, however I was in the need for a slightly different setup without LVS and Loadbalancer.
I was looking for a simple solution based on a traditional round- robin DNS to address webservers in an ACTIVE / ACTIVE setup. Furthermore the standard requirement says: keep it simple ;-)
The script is written in php, maybe not everybody's first choise when thinking of Linux Systems and or System Administration, however a good portion of Clusters
are out there for the purpose of serving php webpages from a mysql database. For this reason I wrote the script in a dualistic way, first to manage the nodes, second to provide simple status info
through a web page.
Advantages: Obvious it is a simple, quickly to setup configuration. Installation concerns only HeartBeat + this script (provided you already have php- cli and mysql).
Disadvantages: If your nodes cannot take over the complete / full load from another node, a load- balancer will probably be better for you. This setup will cost you the full load twice on
fail- over per node, i.e. your average load on your nodes should not exceed 50%.
Give it a try (download), I have it currently running in a 4 nodes cluster and it seems to work fine
Kees van Veen