Author Archives: George Valentin Voina

Set up automatic #Oracle database back-up using #RMAN

By | September 19, 2017
0 Comment

There is a very easy method of setting up on Linux an automatic back-up for Oracle by using database procedures, RMAN and scripts. STEP 1: Define a back-up script Create in /home/oracle/backup.sh a script file with the content: #!/bin/bash export ORACLE_HOME=/home/oracle/app/oracle/product/11.2.0/dbhome_1 export PATH=$PATH:$ORACLE_HOME/bin export ORACLE_SID=prod rman target / CMDFILE=/home/oracle/bin/backup.rman LOG /data/oradata/backuplogs/rman-`date -I`.log exit 0 Where… Read More »

#DRBD investigate and solve a sudden Diskless issue

By | September 19, 2017
0 Comment

Even when you think that you know something well enough you discover that there are some corner cases you never encountered. This is the main reason I like IT system administration tasks, you never get bored. This post is about one of this corner cases in a DRBD setup described in post #DRBD based disk… Read More »

#Docker images cleanup

By | September 17, 2017
0 Comment

CASE 1: If you use multi-stage docker builds you will end up with lots of un-tagged images. The proper way to clean the intermediary leftover images is: docker rmi $(docker images -f “dangling=true” -q) CASE 2: If you want to clean up all the old images for which you no longer have any instantiated container… Read More »

#Edgerouter: Force restart a PPPOE connection.

By | September 15, 2017
1 Comment

One of my internet service providers uses PPPOE for the internet connection. Sometimes if the physical connection is down for a long time the pppoe0 interface is no longer reconnecting or is stuck (looks like connected but no traffic passes through it). I found out that the problem is solved by force reconnecting it through… Read More »

Portable #RaspberryPI #Docker #Swarm – Static IP, Ethernet based, #Portainer

By | October 14, 2017
0 Comment

As I discussed in post Portable #Docker #Swarm made of #RaspberryPI – Updated hardware there were several hardware updates done to the swarm. One of the updates was adding a switch and connecting all the Raspberry PIs to the switch. First version of the Docker Swarm was done using the wifi connections of the PIs.… Read More »

Setup #Eclipse as #go IDE in Linux

By | August 28, 2017
1 Comment

I like Eclipse and I used it for many years on Linux for Java developement. I wanted to test how go(golang) works but I did not like all the suggested IDEs, you know the “cool” ones. I wanted to be able to use Eclipse. By default eclipse is not go oriented but with some small… Read More »

Portable #Docker #Swarm made of #RaspberryPI – Updated hardware

By | October 14, 2017
0 Comment

I wanted to update my hardware setup for the Docker Swarm cluster from post Portable #Docker #Swarm made of #RaspberryPI. The idea was to make it more portable, more reliable and a bit faster. The following steps were done: Add ethernet support The original setup used a small Edimax router with the Raspberry Pi nodes… Read More »

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

By | August 22, 2017
0 Comment

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.it -> nas1 hosted wordpress URL2: https://blog.voina.it/store -> nas2 hosted store with URL https://nas/store URL3: https://blog.voina.it/doc -> nas4 hosted wiki with URL https://nas4/wiki How can we do this… Read More »

Blog Links: A fabulous description of the migration of GitHub to Kubernets and other GitHub news

By | August 18, 2017
0 Comment

Finally the description of the migration of GitHub to Kubernets. This is so nice when you see open source getting used in the huge scale services. Kind of makes it easier for you to push this kind of stuff in the conservative IT business industries. Enjoy the article Kubernets at GitHub A wonderful new GitHub… Read More »

#Biometric #authentication is useless and dangerous alone

By | October 14, 2017
0 Comment

Again and again the same myths and misunderstandings resurface from time to time. I noticed again a misplaced hype in an article shared on twitter about how biometric authentication will simplify banking. I have to share again something I learned many years ago when I was junior research student in a computer security group and… Read More »