Category Archives: Application Servers

XA datasources with #WebSphere and #Oracle

By | December 5, 2017

When using XA data sources with Websphere and Oracle we must grant to the Oracle user rights to perform XA recovery. STEP 1: Create an XA datasource AdminTask.createJDBCProvider(‘[-scope Node=’+ node +’,Server=’+serverName +’ -databaseType Oracle -providerType “Oracle JDBC Driver” -implementationType “XA data source” -name “‘+jdbcXAProviderName +'” -description “Oracle JDBC Driver (XA)” -classpath [${ORACLE_JDBC_DRIVER_PATH}/ojdbc7.jar ] -nativePath “”… Read More »

#nginx proxy_pass an URI to another server with a different URI

By | August 22, 2017

Nginx can be used very nicely to aggregate resources after the same fronted by using it as a proxy. I want my set-up to be like: URL1: https://blog.voina.org -> nas1 hosted wordpress URL2: https://blog.voina.org/store -> nas2 hosted store with URL https://nas/store URL3: https://blog.voina.org/doc -> nas4 hosted wiki with URL https://nas4/wiki How can we do this… Read More »

Hidden Oracle dependencies when running under #Docker on Fedora/CentOS/RedHat Linux

By | June 28, 2017

There are some hidden dependencies of running oracle database in a docker container under Fedora/CentOS/RedHat Linux. STEP 1: Kernel parameters Because the Oracle engine from the Docker container uses in fact the kernel of the host machine we cannot escape the need to set up some kernel parameters on the host. On the host machine… Read More »

#Docker #Jboss dies with java.lang.OutOfMemoryError: Metaspace after several redeploys

By | May 26, 2017

There is an annoying issue with a Jboss EAP 7 Docker container I am using. After 3 deploys of my ear package I hit the “java.lang.OutOfMemoryError: Metaspace” issue. According to RedHat Solution 2038983 this is a known issue caused by: Root Cause The Metaspace is being exhausted. Either it is undersized, or there is a… Read More »

Glassfish MQ: Secure, database backed GlassFish MQ for high volume applications

By | February 8, 2017

GlassFish MQ is a very powerful messaging server solution if correctly configured. By default the MQ server is defined to store the content of queues on files on disk, is accessible through insecure connections and has lots of limitations for message size or number of consumers/producers associated with a queue. This default setup is OK… Read More »

#Apache: Use #letsencrypt.org certificates with an apache server behind a secure reverse proxy

By | March 8, 2017

As I described in a previous post Apache: How to use reverse secure proxy to chain secure apache servers – updated I have a configuration of chained secure apache servers, where one of the servers provides https resources but also acts as a reverse proxy for another server providing https resources. On the first server… Read More »