Infrastructure at your Service

All posts by Mouhamadou Diaw

Mouhamadou Diaw
Consultant

Mouhamadou Diaw has more than ten years of experience in IT domains. He is specialized in Oracle technologies (engineered system, architecture, backup and recovery, high availability, security, audit etc.). Mouhamadou Diaw is Oracle professional Certified (8i, 10g, 11g, 12c), Oracle RAC 11gR2 Certified Expert , Oracle Database 11g Security Certified and CISA (Isaca). He received a Doctorate in Heat and Humidity Transfer of INSA Toulouse, France. His branch-related experience covers Insurance, Retail, International Organizations, Transport & Logistics, etc.
Mouhamadou Diaw

Amazon Web Services: Upgrade to Dbvisit Standby 8

By | Cloud | No Comments

In a previous blog we installed Dbvisit Standby 7 on two AWS linux instances. In this article we are just upgrading to Dbvisit Standby 8. The first thing is to stop on both nodes dbvnet and dbvserver on both servers [oracle@primaserver dbvnet]$ ps -ef|grep dbv|grep -v grep oracle 2062 1 0 04:53 ? 00:00:02 /u01/app/dbvisit/dbvserver/dbvserverd oracle 2064 2062 0 04:53 ? 00:00:00 /u01/app/dbvisit/dbvserver/dbvserverd oracle 2131 1 0 04:54 ? 00:00:00 /u01/app/dbvisit/dbvnet/dbvnetd oracle 2132 2131 0…

 
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Mouhamadou Diaw

Installing Dbvisit Standby 7 between two AWS Linux Instances

By | Cloud | No Comments

Dbvisit is compatible with Amazon Cloud. In this article we are going to talk about installation of Oracle SE2 and Dbvisit Standby 7 between 2 AWS linux instances. We suppose that ssh equivalence is configured for user oracle used for dbvisit installation. First we have to install oracle software on both servers: primaserver and standserver. To Install oracle-rdbms-server-12cR1-preinstall.x86_64 package yum can be used to configure the repository [root@primaserver yum.repos.d]# wget http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol7 -O /etc/pki/rpm-gpg/RPM-GPG-KEY-oracle –2016-11-14 03:52:34–…

 
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Mouhamadou Diaw

Managing My Amazon Web Services Redhat Instance

By | Cloud | No Comments

In a precedent Blog I talked about how to create an AWS linux instance. Some questions can be: How to create a new user and to connect with, how to transfert files from my workstation, how to connect to my oracle instance from my workstation and so on. In this blog I am going to deal with some basic but useful  administration tasks. Changing my hostname One thing we will probably do is to change…

 
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Mouhamadou Diaw

Linux Instance in Amazon Web Services (AWS)

By | Cloud | No Comments

In this article I will talk about how to create a linux machine in the cloud amazon AWS. For testing a trial account can be created. Once registered, we can connect by using the “Sign In to the Console” button To create an instance, let’s click on EC2 under Compute And then let’s use the Launch Instance button We can see the templates  for building our machine. In our exemple we are going to use…

 
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Mouhamadou Diaw

Sharding with PostgreSQL

By | Database Administration & Monitoring | 4 Comments

In this article we are going to talk about sharding in PostgreSQL. What is sharding, Sharding is like partitioning. The difference is that with traditional partioning, partitions are stored in the same database while sharding shards (partitions) are stored in different servers. Below is an example of sharding configuration we will use for our demonstration PostgreSQL does not provide built-in tool for sharding. We will use citus  which extends PostgreSQL capability to do sharding and…

 
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Mouhamadou Diaw

Understanding Row Level Security on PostgreSQL

By | Database Administration & Monitoring | One Comment

In this article we will talk about a nice feature Row Level Security on PostgreSQL. We are using EDB Postgres Advanced Server 9.5. Suppose that I am a team manager and that employee bonus are stored in a table Bonus. I want that each employee can see only data related to him and not data for other. How Can I implement this? I can simply use Row Level Security. Let’s go on. Below is the structure of my…

 
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Mouhamadou Diaw

SharePlex Compare and Repair commands

By | Database Administration & Monitoring | 2 Comments

Reading Franck Pachot blog about comparing source and target in a Dbvisit replication (http://blog.dbi-services.com/compare-source-and-target-in-a-dbvisit-replication/), I decide to write a small article about how we can do same thing with SharePlex. Indeed SharePlex provides built-in commands to compare and repair synchronization. Below is our configuration file. We are just replicating table article to article_rep. Both tables contain 2000000 rows datasource:o.SPLEXDB #source tables target tables routing map titi.article titi.article_rep atlasrep2@o.SPLEXSTR2 From the source let’s insert 2 rows…

 
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Mouhamadou Diaw

Manage DDL inside SharePlex

By | Database Administration & Monitoring | No Comments

In a precedent blog (http://blog.dbi-services.com/discovering-shareplex-for-oracle/) about SharePlex, we presented how to setup a replication between 2 environments. In this article we will try to see how SharePlex deals with replicating DDL statements. Before starting we present below our environment and our configuration file. We are just  replicating scott_atlas to scott_atlasrep2. We suppose that SharePlex is already configured. Server Name Database Name Oracle Version What atlas.localdomain SPLEXDB 12.1.0.2 Source atlasrep2.localdomain SPLEXSTR2 12.1.0.2 Target [oracle@atlas config]$ cat ddl_config_atlasrep2.cnf datasource:o.SPLEXDB…

 
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Mouhamadou Diaw

Discovering SharePlex for Oracle

By | Database Administration & Monitoring | No Comments

Nowadays, replicating data is very important. Many tools exist in the market (Goldengate, Dbvisit …). In this article we talk about a Dell Product tool that can be used for data replication: SharePlex. The goal is to show how it is easy to setup a SharePlex environment for replicating data. After installing the software we will replicate scott schema to a target database into a new schema named scott_str1 We present below the environment we use Server Database…

 
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Mouhamadou Diaw

Install Oracle 12c Flex Cluster Easily

By | Database Administration & Monitoring | No Comments

To install a flex cluster (or a flex ASM)  Grid Naming Service (GNS) is required. A GNS can be configured with dynamic public networks (DHCP) for VIP. This method is suitable for a big number of nodes.In this case GNS domain delegation is mandatory. In case of a few number of nodes, GNS can be configured without domain delegation. In this case we have to define manually all VIP addresses (like in a standard cluster)…

 
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