Infrastructure at your Service

Category Archives: Operation systems

Oracle Team

List usernames instead of uids with the ps command for long usernames

By | Database management, Operation systems | One Comment

By William Sescu Have your ever faced such a situation. You have usernames in your /etc/passwd file with more than 8 characters. This is no problem for Linux at all, usernames may be up to 32 characters long, only your ps output might look a little scrambled. It shows you the uid instead of the username like in the following example: $ id uid=20001(longuser01) gid=10002(oinstall) groups=10002(oinstall) $ sleep 1000000 & $ ps -ef | grep…

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Oracle Team

How to do a Filesystem Resize (ext3/ext4) on Redhat running on VMware

By | Database Administration & Monitoring, Operation systems | No Comments

By William Sescu A filesystem resize can be done in several ways, online, offline, with LVM2 or without LVM2.  However, this blog will describe how to do an online resize of ext3/ext4 filesystems where a virtual disk (vmdk) is online added to a VMware Redhat guest OS. So let’s start with the online filesystem resize of ext3/4 filesystems on the Redhat guest OS.  A new virutal disk (preferably an eagerd zero thick on VM running…

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Shrinking Oracle VM VirtualBox with Zerofree

By | Hardware & Storage, Operation systems | No Comments

In this blog I would like to talk about Shrinking a Virtual Machine with Oracle databases and MySQL which is install. Unfortunately, whilst Virtual Box will dynamically expand the hard drive as it’s required, it won’t dynamically shrink it again if you free up space in the VM. The good news is You can shrink a dynamic Virtual Box disk image and so reduce the size of your VM infrastructure. I have use the Zerofree…

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Stéphane Savorgnano

SCOM: schedule group maintenance task with PowerShell

By | Database Administration & Monitoring, Operation systems, Technology Survey | No Comments

In my last blog post, here, I spoke about how to place SCOM group in maintenance mode. This script is really interesting with an integration in Windows Task Scheduler. At the end, the main purpose is to plan a maintenance window of our different servers. Let’s see how we can do that with PowerShell script. First, I try to use the cmdlet Register-ScheduledTask, which can be used to register a scheduled task definition on a…

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Stéphane Savorgnano

SCOM: change group state to maintenance mode with PowerShell

By | Database Administration & Monitoring, Database management, Operation systems, Technology Survey | No Comments

Some weeks ago, I wrote a blog post about the creation of SCOM groups in order to subscribe to alerts. Subscribe to alert is mandatory, of course, to be able to receive alerts concerning our group. But during operations like an update, a patching, …, we don’t want to be spoiled by lots of alerts. To avoid those unexpected Emails, we need to place our group and so, objects contained in this group, in maintenance…

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David Barbarin

Windows Failover Cluster : Introduction to paxos tag

By | Database Administration & Monitoring, Operation systems | No Comments

A couple of days ago, I was in charge to install a new SQL Server AlwaysOn and availability group with one of my colleague Nathan Courtine. During the installation, we talked about testing a disaster recovery scenario where we have to restart the Windows Failover cluster in forced quorum mode. Restarting a WSFC in such mode implies some internal stuff especially for the cluster database data synchronization between nodes. The WSFC uses internally the paxos…

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VM Linux – Device not found : Network unreachable

By | Database Administration & Monitoring, Operation systems | No Comments

Recently I exported an Oracle Virtual Box VM as an “.ova” file. When the file was imported again I faced issues with the network devices inside the VM. This post is about what I experienced and how I resolved it. In my example I have two networks devices configured for the VM in the Virtual Box: When I logged in I found that eth0 and eth1 are not available: [root@MYSQL ~]# ifconfig lo Link encap:Local…

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Georges Grey

Stay tuned with kernel parameters

By | Database Administration & Monitoring, Operation systems | No Comments

Why does the sysctl.conf value for swappiness on Oracle Linux 7.x not survive a reboot For a project I applied the dbi services best practices for Oracle databases. One of these is to adjust the swappiness parameter. We recommend to use a very low for the swappiness value like 10 or even lower to reduce the risk for Linux to begin swapping! Swapping on a database server is not a problem per se, but it generates activity…

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David Barbarin

Windows Server 2016: Introducing Storage Spaces Direct

By | Hardware & Storage, Operation systems | 5 Comments

Have you heard about Storage Spaces introduced by Windows Server 2012? Well, this is a very interesting storage feature that allows us to deal with functionalities like storage virtualization, RAID capabilities, thin or thick provisioning, cluster shared volume (CSV), efficiently file repair and so on. In addition, the Windows 2012 R2 version has also introduced some enhancements like storage tiering, write-back caching, datadeduplication, parity space support for failover clusters, JBOD enclosure awareness… A bunch of…

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Daniel Westermann

Getting started with Ansible – Preparations

By | Database Administration & Monitoring, Operation systems | No Comments

When your infrastructure landscape becomes larger and larger you definitely need a tool which helps you in managing your servers, no matter if pḧysical or virtual, running in the cloud or not. One tool (many others are around) which assists you in provisioning, configuration management and mass deployment is Ansible. If you look at the man page you can find this sentence: “Ansible is an extra-simple tool/framework/API for doing ‘remote things’ over SSH.”. What is…

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