oracle rac concepts

, the 11.2.0.1 RAC that is installed on the virtual machine is chosen 11.2.0.1 because of problems with public IP and private network segments. During the installation instance, the computer crashes and restarts, and CRS fails to start. [Root@rac1 bin]#./crsctlstart CRS Crs-4124:oracle highavailability Services startup failed. Crs-4000:command startfailed, or completed with errors. [Root@rac1 bin]# Ps-ef|

security of the database, once lost, it is difficult to find back. Therefore, it is hoped that through the establishment of database clusters, the redundancy of the data set, the backup data to ensure security. Classification of database clusters Database cluster technology is a technology that combines multiple servers to form a cluster to achieve comprehensive performance better than a single large server, this technology can not only meet the need of application, but also save the investment

After two tests, RAC is very fragile.1. Remove the public network cable of Rac1 and stand next to rac2 to see the changes. It is found that the VIP is quickly converted to rac2 and users can still use it.2.1 minutes later, rac2 restarts automatically. Check that the shared disk cannot be mounted. Another colleague is in config San and cannot determine whether the shared disk is actually faulty.3. Simply perform a more aggressive test, remove the power

RedHat EL5 Installing the Oracle 10g RAC--oracle Software InstallationSystem environment:Operating system: RedHat EL5Cluster:oracle CRS 10.2.0.1.0Oracle:oracle 10.2.0.1.0: RAC System Architecture650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M00/26/28/wKioL1Np_tziLDXcAAGvUOVml00321.jpg "title=" Rac.png "alt=" W

First, view RAC Environment RAC Architecture, 2 node information Node 1 Sql> Show Parameter instance NAME TYPE VALUE ------------------------------------ ----------- ----------------------------------------------- Active_instance_count integer Cluster_database_instances Integer 2 Instance_groups string instance_name string RACDB1 Instance_number Integer 1 Instance_type string RDBMS Open_links_per_instanc

Tri Hua, Network name DbsnakeOracle ACE Director,acoug Core expert("Tri Hua article series" has been Tri Hua exclusive authorized in the cloud and the official account of the ink will be released, please continue to pay attention to)This article details the connection management in the Oracle RAC environment, and describes what the connect time load Balancing, Runtime Connection load Balancing, connect is C

I. Introduction One of the most effective ways to familiarize yourself with Oracle's true application cluster (RAC) 10g technology is to access an actual Oracle RAC 10g cluster. There is no way to better understand their benefits than simply experiencing them-including fault tolerance, security, load balancing, and scalability. The core of

the Oracle RAC database environment has a lot in common with a single-instance database environment, as well as many heterosexual. The same is true for updates to database patches, which can be done through Opatch. However, patch updates for the RAC environment are updated in several different ways, and even rolling upgrades can be implemented for all nodes in th

instance. Oracle ASM uses Oracle ASM metadata to control disk groups. The Oracle ASM metadata is located in the disk group and contains the following information: Ing between a disk and Its disk group Size of available space on the disk File Name on the disk Location of the extent of the data file in the disk group Redo log that records information about a

Oracle study--oracle 11gR2 RAC CRS startup failureSystem environment:Operating system: RedHat EL5Cluster:oracle 11gR2 GridOracle:oracle 11gR2In a RAC environment, one of the nodes CRSD the process failed to start:[[email protected] ~]$ CRSCTL Check CRSCrs-4638:oracle High Av

Oracle study--oracle 11gR2 RAC CRS startup failure (CRS-4000)System environment:Operating system: RedHat EL5Cluster:oracle 11gR2 GridOracle:oracle 11gR2The following error occurred while initiating a node CRS:[[email protected] ~]# crsctl start CRS Failure at Scls_scr_getval with code 1 Internal Error information:category: -2 operation:opendir location:scrsearch1

Oracle RAC runs on top of the cluster, providing the highest levels of availability, scalability, and low-cost computing power for Oracle databases. If one node in the cluster fails, Oracle can continue to run on the remaining nodes. Oracle's main innovation is a technology called cache merging. Cache merging enables n