Author Archives: George Valentin Voina

Optimizing DELETE operations on big tables in #DB2

By | November 21, 2017

Deletes go very slow if the log buffer size is too small and we delete lots of data from big tables. It is very important to have the right settings for log buffer size to avoid having to frequent writes to the disk, writes that cause a high IO traffic that will slow down the… Read More »

Fix #DB2 SQL1639N ( SQLCODE=-1639, SQLSTATE=08001, SQLERRMC=null) authentication issue

By | November 21, 2017

After migrating my full DB2 backup (binaries and data) to a new server I got into several issue. One was already described in the previous post here. ISSUE: Even after fixing that start issue I was still not OK. My WebSphere data source that linked to the DB2 instance was not responding. Trying to ping… Read More »

Fix #DB2 Communication protocol failed to start issue: SQL5043N

By | November 21, 2017

I moved my DB2 installation to a new server from a full back-up. After performing all the necessary steps: 1. Recreate the necessary users: db2inst1, db2fenc1, db2das1 2. Give ownership to their home directories ISSUE: I tried to start the instance. I logged in to the db2inst1 user and started the database. This was the… Read More »

Automatic remote backup using cron and #OwnCloud

By | November 26, 2017

Setting up a backup is important and at the same time the most neglected task. One quick solution for a remote backup is using OwnCloud. If you already have your OwnCloud server or just an account the following short steps can be done. STEP 1: Gather your data Lets gather the data to be back-ed… Read More »

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 »

#Websphere SIB issues when running Websphere in a #Docker container

By | November 14, 2017

When running a Websphere Application server instance in a docker container, if the Service Integration Bus (SIB) is defined to store all the messages and data in an external database there is an issue caused by the way the bus is created. When the SIB is initialized the given name depends on the hostname of… Read More »

Bind #Docker container ports to virtual interfaces to simulate cluster nodes

By | November 8, 2017

My setup implies that I have 3 almost identical application nodes (running as containers) that are part of a cluster and they need to be mapped to different external IPs (not part of the docker ingress network) because they are added in a cluster configuration external to docker. The default behavior of port binding is… Read More »

TCP keepalive: what is it, why do you need it, how to configure it on #Linux

By | November 7, 2017

As you are aware, no service runs alone on some server. You always have to take into account the communication layer between your server and client services. One of the most tricky thing a lot of people overlook is the “housekeeping” of the communication layer. In a properly setup enterprise environment your communication layer (firewalls,… Read More »

#RaspberryPi python games for #Pimoroni Unicorn HAT HD

By | November 7, 2017

There are some nice demos that come with Pimoroni Unicorn HAT HD library but if you want something more fun you can have interactive applications. How about GAMES ? I stumbled over a thread Unicorn HAT Demo Ideas where someone was asking foe ideas of demos for the standard Unicorn HAT. Two of the best… Read More »

#RaspberryPi with #Pimoroni Unicorn HAT HD

By | October 21, 2017

This pumped up Pimoroni Unicorn HAT HD is an incredible toy. The content of the kit looks like the following: – a 256 RGB LED pixels in a 16×16 matrix. Pixels driven by ARM STM32F and three STP16CPC26 LED drivers – Bundled ninja diffuser – Nuts(4) and bolts (8 + 3 spares) I was able… Read More »