Life Magazine’s motto

“To see the world, things dangerous to come to, to see behind walls, to draw closer, to find each other and to feel. THAT IS THE PURPOSE OF LIFE.”

“Poznávat svět, i nebezpečí co to přinese, překonávat hranice, sbližovat se, poznávat druhé a cítit. TO JE SMYSLEM ŽIVOTA.”

— Life Magazine’s motto (The Secret Life of Walter Mitty)

Digital IBMer 2014 – Internet Explorer 11 facing like IE7 issue

From server perspective everything with Digital IBMer 2014 works fine. But end-users reported strange behavior: some pages were empty for them.

Digital IBMer 2014 IE11 issue     Digital IBMer 2014 in FF is ok

Steps taken

  1. Tried to reproduce the issue on test environment … issue was not reproducible, it appears in production only
  2. Checked IHS (Apache) access and error logs … they were clear, no issue
  3. Checked connection statistics (netstats) to see if we are not hitting limits … stats were OK
  4. Tried to reproduce issue in Firefox with Firebug … issue not reproducible, all requests made to server were returned with HTTP 200 (OK)
  5. Tried to reproduce issue in IE11 with Fiddler … issue reproducible, but Fiddler shown no issue, all requests were returned again with HTTP 200 (OK)
  6. Checked if files in cache are equal to files on server … files were OK
  7. Check of page in IE using F12 Developer Tools … Network tool confirmed all files were received OK, Console shown no issues, in DOM Inspector everything seemed all right


As issue was reproducible only in IE11 and not in other browsers (IE9, Firefox, Chrome, Safari), we were sure issue is not on our servers, but on the course side. We engaged developer of the course, guy from India, DOJO and browser expert. It took him about 10 minutes to identify the issue.

IE11 Compatibility Mode settings

Problem was that somehow IBM internal servers made it to the Microsoft compatibility list, and so the production server pages were rendered in IE7 compatibility mode. And this caused Framework malfunction. Helpdesk was instructed to suggest to users to turn of both checkboxes in Compatibility View settings and make sure is not listed within Compatibility Mode Websites, what resolved the issue.

Digital IBMer 2014 – Context and History

As you (maybe) know, I work in IBM on development and support of Learning Management System. Every year we are faced with challenge of so called Digital IBMer course. It’s course which educates IBMers on the latest cybersecurity threats, and all IBM employees need to go through it every year. From our perspective that means few thousands unique users in addition to standard daily load, and usually all those users try to make the course in about same timeframe (1-2 peak hours).

Digital IBMer 2012 was mainly about tuning our WebSphere App Server and DB2 configuration. During Digital IBMer 2013 shared proxies were the main blocker (there is a limit of incoming connections for each application).

For this year we worked pretty hard since last October to make whole environment ready. We’ve got our own dedicated proxy server, we’ve ran extensive performance testing, there was setup a super-cool monitoring tool ITCAM to help us analyze the system, we’ve added some other monitors on OS level based on various performance analysis experts advices, and in cooperation with AIX, DB2 and WAS L2 support we’ve tuned our environment settings. Simply said – we’ve made everything ready.

This should have been first year without any issues… 🙂

WordPress šablona Twenty Fourteen a problém s českými fonty

Po instalaci WordPressu s novou šablonou Twenty Fourteen jsem narazil na problém, že se slova s diakritikou zobrazovaly špatně. Na vině je v šabloně použitý font Lato, který nepodporuje rozšířenou latinku (Latin Extended), což je pro správné zobrazování češtiny třeba.

Twenty Fourteen s fontem Lato Twenty Fourteen s fontem Open Sans

Aby vše fungovalo jak má, je nutné nahradit tento font jiným, Latin Extended podporujícím. Já se po krátkém průzkumu rozhodl pro Open Sans, který je dostupný přes Google Fonts.

K tomu stačilo jen dle návodu How to Create a WordPress Child Theme vytvořit “podtéma”, které přejímá všechny vlastnosti originálního Twenty Fourteen (takže budoucí aktualizace nebudou mít na úpravu vliv), toto nainstalovat do WordPressu, a bylo hotovo.