An EdgeRouter firmware update from 1.8.5 to 1.9 broke my L2TP based VPN. After the update my l2tp connection to local subnets was no longer working. Note that I have a load balancing setup with eth0 and eth1 being the load balanced WAN interfaces. It seems that due to the changes done for the l2tp… Read More »
After seting up Security Onion as my home data center IDS (see https://blog.voina.org/data-center-ids-solution-using-security-onion/) I started to integrate monitoring of other resources to it. The first idea was to add the monitoring of my EdgeMax routers. Security Onion has a syslog-ng service that is able to receive client syslog data. Then we can visualize this data… Read More »
An enterprise environment has to be monitored for external threats. There are a lot of very expensive IDS (Intrusion Detection System) that do this for you but you can set up in a production environment a very good solution for zero cost. The strength of an IDS is given by the IDS threats database, a… Read More »
Sometimes we need to find specific things in application vast logs, sometimes 10 or 20 rotated logs each hundred of MBs each. For a quick search without using some specialized log viewer we can use the very powerful bash text processing commands. Problem: We have 10 log files each 100MB and we need to find… Read More »
In some cases while optimizing code to minimize the database footprint of a Java EE application we get to the point of trying to get rid of duplicate data. In a lot of cases several steps of the processing flow tend to store partially processed data or states of data and in a lot of… Read More »
Yet another thread of DB2 errors from an EJB application that connects to a DB2 instance. The reported thread of errors: [7/13/16 12:46:38:670 IST] 00000098 SqlExceptionH Z org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions [jcc][t4][102][10040][4.19.26] Batch failure. The batch was submitted, but at least one exception occurred on an individual member of the batch. Use getNextException() to retrieve the exceptions… Read More »
Sometimes Java and databases do not use the same standards to represent data. This can lead to strange exceptions for which sometimes can be hard to pin point the cause. We have the following Exception reported in the enterprise application log. Let’s analyse the errors. [7/13/16 12:46:32:752 IST] 00001456 SqlExceptionH Z org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions SQL Error:… Read More »
Configurations of a Windows Fail Over Cluster can be done entirely from the GUI but as we know this is valid for the simple setup. The GUI is limited to the easy cases, not for more uncommon cases. I already covered the case of the Active Directory Detached Cluster that can be created only using… Read More »
After connecting my two sites using IPSEC see ipsec site-to-site with virtual tunnel interface/ it is easy to ssh to the remote site and OpenVPN see OpenVPN site to site Let us go a step further and activate also remote desktop. I want to be able to connect from my Linux machines but also from… Read More »
Especially when creating a demo image of an enterprise system we want to have a smaller footprint than the full system that was cloned. The same is true when the image is used for volume benchmarks. Between different benchmark sessions we want to clean the old test data and maybe in the end we want… Read More »