About Golden Gate

-
Golden gate:
===========

Golden gate software was founded in the year 1995 and name after famous golden gate bridge
Golden gate was founded by eric fish and tod davidson


Golden gate features:
====================

Real time data replication is one of the basic feature of golden gate
It provides high availability by acting as live stand-by target for a primary target
It provides  zero downtime upgrades and migrations
It provides live reporting for the operational databases


Golden gate Processes:
=====================
Manager process
Extract Process(capture process)
replicat Process
Trail files
Data Pump
Server Collector


Extract Process:
===============
It reads the data from the online redo logs of the database and typically does not require connection to the database.
The extract process will regularlily checkpoint its read and write position, typically to a file.

Trail  Files:-
============
Trail files basically contains the canonical format of collected online trasactional data from the redologs of the database by extract process.
These files will be existing at source and target locations typically called as local fie and remote file.
we can configure Golden gate without trail files by directly transferring captured online redolog data to target server , but this process is not recomended
local trail file will be helpful during recovery and more even we can  resend the trail files to target server using DataPump

DataPump:
========
This is an additional process along with extract process as it takes responsibiity of sending local trail files to target server using TCP


Server Collector:
===============
Server Collector process runs at target server , collecting information of local trail file and writes to remote trail file.

Replicat Process:
================
This process reads remote trail file and applies to target database in the form DDL and DML

Manager Process:
================
Manager process runs on both source and target servers .  It control starting and stopping of the proceses , monitors and then generates events.




Comments

Post a Comment

Popular posts from this blog

Understanding Terraform

-
 Terraform is a tool used  for building, changing, and versioning infrastructure safely and efficiently. A Terraform can manage multiple cloud services using a provider plugin  Terraform work flow? Terraform work flow will be comprised of validate -> plan -> apply and finally destroy. what is the important file of terraform which records the actions of Terraform apply? For every Terraform execution the action will be recorded in a file called Terraform state file .  The terraform init command is used to initialise a working directory containing Terraform configuration files. During init, the configuration is searched for module blocks, and the source code for referenced modules is retrieved from the locations given in  their source arguments. The terraform plan command is used to create an execution plan. It will not modify things in infrastructure. The terraform apply command is used to apply the changes required to reach the desired state of the configur...
Read more

How to make CRS and ASM not to restart after server reboot

-
I have noticed that server rebooting is taking lot of time on a VM machine for every reboot, so I have decided to auto start of the crs and ASM service During this phase I have noticed an attribute called auto_start when I try to execute the below command crsctl stat res -p This AUTO_START attribute is there for several resources like ora.ASM ,ora.crs,ora.DATA_DG it has got 2 options restore(0) , never(2) and always (1) always (1)  Causes the resource to restart when the node restarts regardless of the resource’s state when the node stopped -restore (0)  Does not start the resource at restart time if it was in an offline state, such as STATE=OFFLINE, TARGET=OFFLINE, when the node stopped. The resource is restored to its state when the node went down. The resource is started only if it was online before and not otherwise. -never (2)  Oracle Clusterware never restarts the resource regardless of the resource’s state when the node is stopped. So I have dec...
Read more

How to repair ASM disk header

-
Image
What is ASM disk header corruption? ASM disk header corruption is a loss or damage to the disk header which contains the metadata essential for the operation and availability of an ASM disk group in Oracle. Imagine that you have an ASM disk corruption in any of the ASM diskgroups that have critical business data and the diskgroup has been configured as "EXTERNAL" redundancy, meaning that if one disk is inaccessible the whole diskgroup will be unavailable. Now what? Is your only option to restore it from backup by recreating the diskgroup or are there any other faster ways to recover the data? Here you need to find out whether it’s a complete loss of data in the ASM disk or is it just a header corruption. Hopefully for you, this is just a header corruption. Because, yes, there is a way out!  Below find the steps to restore from the ASM header corruption. Most of the data in the ASM disk header is of interest to that disk only. However, some information in the ASM disk header ...
Read more