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Category Archives: Operation systems

Mouhamadou Diaw

Monitoring Linux With Nmon

By | Hardware & Storage, Operation systems | No Comments

I was looking for tools to monitor linux servers and I found an interesting one nmon ( short for Nigel’s Monitor). I did some tests. In this blog I am describing how to install nmon and how we can use it I am using a Oracle Enterprise Linux System. [root@condrong nmon]# cat /etc/issue Oracle Linux Server release 6.8 Kernel \r on an \m [root@condrong nmon]# For the installation I used the repository epel wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm…

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Oracle Team

Kernel panic – not syncing: Out of memory and no killable processes

By | Operation systems, Oracle | No Comments

By Franck Pachot . This is a quick post to give a solution (maybe not the best one as this was just quick troubleshooting) if, at boot, you see something like: Trying to allocate 1041 pages for VMLINUZ [Linux=EFI, setup=0x111f, size=0x41108d01] and then: Kernel panic – not syncing: Out of memory and no killable processes Pid: 1228 comm: kworker Not tainted 3.8.13-118.17.4.el6uek.x86_64 #2

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Nicolas Penot

Automate OVM deployment for a production ready Oracle RAC 12.2 architecture – (part 02)

By | Database Administration & Monitoring, Database management, Hardware & Storage, Operation systems, Oracle | No Comments

In this post we are going to deploy a R.A.C system ready to run production load with near-zero knowledge with R.A.C, Oracle cluster nor Oracle database. We are going to use the “Deploy Cluster Tool” which is provide by Oracle to perform Oracle deployment of many kind of database architectures you may need like Oracle single instance, Oracle Restart or Oracle R.A.C. This tool permits you to choose if you want an Enterprise Edition or…

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Nicolas Penot

Automate OVM deployment for a production ready Oracle RAC 12.2 architecture – (part 01)

By | Database management, Hardware & Storage, Operation systems, Oracle | No Comments

After having worked with OVM on various architectures I can say that it is a good technology to easily build virtualized environments for production applications. Because it is based on XEN and has simple ways to deal with existing storage (FC, ISCSI, NFS, …) and networking solution (bond, lacp, …) it is a robust and convenient way to virtualized IT infrastructures keeping “bare-metal” performance. Besides, it is an hard partitioning technology which is compliant with…

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Oracle Team

Oracle Linux 7 – How to audit changes to a trusted file such as /etc/passwd or /etc/shadow

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

Linux auditing is quite powerful and a lot of different use cases might be handled via the auditing framework. However, in this blog I would like to show you, how to audit changes on trusted files, like /etc/passwd or /etc/shadow. Of course, you are not limited to these files. You can audit whatever you want. Maybe the sqlnet.ora, the /etc/oratab or Oracle wallets are of more interest in your environment. Before we start, we got…

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Oracle Team

OEL 7 – How to disable IPv6 on Oracle Linux 7 – Follow Up

By | Operation systems | No Comments

By William Sescu This is a follow up to the Blog were I explained how to disable IPv6 on Oracle Linux 7. If you have done all the steps which I have explained here http://blog.dbi-services.com/oel-7-how-to-disable-ipv6-on-oracle-linux-7/  then you have already IPv6 successfully disabled. However, some tools require some special attention afterwards if you want to avoid some ugly warning or error messages. There are so many tools that can use IPv4 and IPv6, but it is…

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Oracle Team

Linux – Securing your important files with XFS extendend attributes

By | Operation systems | No Comments

By William Sescu Let’s say, the tnsnames.ora is a quite important file on your system, and you want to make sure that you notice when someone changes the file. Taking a look at the modification time of that file would be good idea, or not? Per default, the ls -l command show only the (mtime) modification time. In my case, I know that the tnsnames.ora was changed on “Feb 9 11:24″. oracle@dbidg03:/u01/app/oracle/network/admin/ [rdbms112] ls -l…

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Natascha Karfich

vagrant up – get your Oracle infrastructure up an running

By | Database Administration & Monitoring, Database management, Operation systems | One Comment

By using Vagrant to manage your Virtual Machines and Ansible for configuration management and provisioning you can easily automate the setup of your whole test environment in a standardized way. If you have never heard about Ansible and Vagrant I try to give you an idea with the following very short  summary. There is a lot of good information available about Ansible and Vagrant. Please check the provided links at the end of this blog…

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David Barbarin

Dealing with WSFC 2016 quarantine state and availability groups

By | Database Administration & Monitoring, Operation systems | One Comment

I was playing with my lab environment which includes Windows 2016 and SQL Server 2016 and I noticed an interesting scenario while testing cluster node failures. After simulating some network outage scenarios, I was not able to bring back my cluster node online immediately by using traditional way. A quick look at the cluster manager led me to notice something new: A quarantined state value … interesting! But what does it mean exactly? In respect…

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