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Operation systems

Oracle Team

Cause for looping sssd

By | Operation systems | No Comments

In RedHat Enterprise Linux 7, the sssd daemons can connect to active directory servers. Default behaviour is to update DNS entries dynamically. If a statical DNS entry already exists this can lead to a CPU consuming sssd_nss daemon. To prevent this behaviour, the dynamic DNS updates should be switched off with this setting in every doman section of config file /etc/sssd/sssd.conf: dyndns_update = False After that sssd should be restarted to take this change effect.

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Joël Cattin

Red Hat Enterprise Linux 8 – Application Streams

By | Operation systems | No Comments

You may have heard that : Red Hat Enterprise Linux 8 is available for downloading in beta version since few weeks… You want to download it ? Click here. A significant change coming with this new version is the way the applications packages are provided. As you know, up to RHEL7 packages were downloaded via repositories listed in .repo files located by default under /etc/yum.repos.d/. This is still the same with RHEL8, but two new…

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Mouhamadou Diaw

Monitoring Linux With Nmon

By | Hardware & Storage, Operation systems | One Comment

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. [[email protected] nmon]# cat /etc/issue Oracle Linux Server release 6.8 Kernel \r on an \m [[email protected] 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

Configure AFD with Grid Infrastructure software (SIHA & CRS) from very beginning.

By | Cloud, Database Administration & Monitoring, DevOps, Operation systems, Oracle | One Comment

Introduction : Oracle ASM Filter Driver (Oracle ASMFD) simplifies the configuration and management of disk devices by eliminating the need to rebind disk devices used with Oracle ASM each time the system is restarted. Oracle ASM Filter Driver (Oracle ASMFD) is a kernel module that resides in the I/O path of the Oracle ASM disks. Oracle ASM uses the filter driver to validate write I/O requests to Oracle ASM disks. In this blog I will…

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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 | 2 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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