Author Archives: George Valentin Voina

iSCSI SAN resources configuration as shared disks in a cluster environment, replicated also with DRBD

By | April 24, 2017

The following configuration was created to use the iSCSI exported resources from a NetApp storage device as shared disk resources in a Linux cluster environment. The same resources are also replicated to a remote cluster using DRBD disk replication. The production environment contains four exported SAN resources which will be used as shared resources in… Read More »

DB2: Finding and adding indices

By | February 8, 2017

DB2 has a very powerful tool (db2advice) to determine necessary indices for your DB2 database. Having a good index can have a very big boost in performance in any application. If working with high throughput systems it is crucial to have the right index. Note that my databse user is db2inst1 and database name MMS.… Read More »

DB2 Sqlcode: -964, Sqlstate: 57011 (transaction log for the database is full)

By | February 8, 2017

I got this error while doing some performance tests on a high volume system using DB2. This is the usual unintuitive error that IBM likes to give to the users 🙂 IN plain English this means that “The transaction log for the database is full.” This appears when you have to execute UPDATE or INSERT… Read More »

Windows 10 NIC teaming – disabled by MS for client SKU

By | October 21, 2017

My Dell XPS 8700 desktop comes with a Realtek PCIe GBE Family Controller. By adding another 2 port Realtek PCIe GBE Family Controller I wanted to get a faster connection to the servers. Note that each of the HP Microserver servers has a 2Gbps connection obtained by NIC teaming the 2 port adapters in Linux.… Read More »

EdgeRouter : Dual WAN with Hair Pin

By | January 7, 2016

Starting with firmware version 1.4 EdgeRouter can be configured in a dual WAN setup using a very simple wizard. Then to configure some port forwarding rules to access the internal web server or VPNs there is a nice GUI setup window. Note that I experienced frequent switches between the main WAN and the backup WAN.… Read More »

EdgeRouter : Activate the DNS filtering of add servers

By | February 10, 2017

Everybody hates Add Servers so all my PC and mobile browsers use AddBlock+, but still I do not want the extra traffic that is done even by using ad blockers. The best solution is to simply block from the EdgeRouter Ubiquiti Networks ERLite-3 EdgeRouter Lite the ad sites. The best guide for this is: EdgeMAX… Read More »

EdgeRouter : activate CLI root account

By | April 1, 2016

To be able to do several CLI configurations administrator (root) account must be activated. By default EdgeRouter has this account disabled. It seems that even if is activated a firmware upgrade will revert it to the default configuration (disabled). To activate the root account follow the tutorial: EdgeMAX – What is the root account password?… Read More »

Fedora Linux: LVM Single Drive to LVM RAID 1 Mirror Migration

By | March 3, 2017

All started when I wanted to have a true HA configuration for the server nodes. That implies that not only the storage of each server is a RAID10 setup, but also the boot and root resources are in a RAID1 configuration. I started to use an old and known tutorial to convert from standard installation… Read More »

EdgeRouter: Configure dual WAN with EdgeRouter POE

By | January 7, 2016

As more and more “smart home” devices got installed around the house the need to have 24/7 Internet connection was more and more a necessity. The solution I choose was to have a back-up mobile Internet for the home. To make this completly transparent to the “Internet of things” from the house this backup had… Read More »

Relax and Recover with bareos

By | June 30, 2015

A good way to backup the OS of the servers is to use rear Relax and Recover. Following are the steps to ensure that we have a proper rescue data set for both servers. STEP 1: Install rear from the Fedora repo on both nas1 and nas2 [root@nas1 ~]# dnf install rear [root@nas2 ~]# dnf… Read More »