What is split brain in RAC?
Split Brain is often used to describe the scenario when two or more nodes in a cluster, lose connectivity with one another but then continue to operate independently of each other, including acquiring logical or physical resources, under the incorrect assumption that the other process(es) are no longer operational or …
What is RAC interview questions?
Part 1 – Oracle RAC Interview Questions (Basic)
- Q1. Explain split brain?
- Q2. Explain the use of VIP and OLR?
- Q3. What do you understand by rolling upgrade?
- Q4. What do you understand by cache fusion?
- Q5. What are the uses of RAC?
- Q6. Discuss OEM tools?
- Q7. What is the ASM Metadata backup technique?
- Q8.
What is scan IP in Oracle RAC?
Single Client Access Name (SCAN) is a feature used in Oracle Real Application Clusters. environments that provides a single name for clients to access any Oracle Database running. in a cluster. You can think of SCAN as a cluster alias for databases in the cluster. The benefit.
How many scan listeners in RAC?
RAC instances register to SCAN listeners as remote listeners. Oracle recommends assigning 3 addresses to SCAN, which will create 3 SCAN listeners, though the cluster has got dozens of nodes.
What is CSSD in Oracle RAC?
Oracle Cluster Synchronization Services daemon (CSSD) Cluster Ready Services daemon (CRSD), which is the main engine for maintaining availability of resources.
What is GCS and GES in RAC?
The GCS and GES are integrated components of Real Application Clusters that coordinate simultaneous access to the shared database and to shared resources within the database and database cache. GES and GCS together maintain a Global Resource Directory (GRD) to record information about resources and enqueues.
What is background process in Oracle RAC?
Background Processes Specific to Oracle RAC
| ACMS | Atomic Control File to Memory Service |
|---|---|
| GTX[0-j] | Global Transaction Process |
| LMON | Global Enqueue Service Monitor |
| LMD | Global Enqueue Service Daemon |
| LMS | Global Cache Service Process |
How does Oracle RAC startup sequence?
1) INIT : INIT is the very first file to be checked to be start at the time of the operating system boot,it is system and service manager for the Linux , Aix or any other Linux flavor. This service start and stop through script which is stored in the /etc/init. d directory .
What is difference between scan IP and VIP?
SCAN virtual IP addresses (VIPs) function like node VIPs. However, unlike node VIPs, SCAN VIPs can run on any node in the cluster. Clients (users or applications) that connect using a SCAN instead of a node VIP name or address do not have to update the list of node names or addresses in their local tnsnames.
How can I do load balancing in RAC?
Client Level Load Balancing : In Oracle RAC we can specify LOAD_BALANCE parameter in tnsnames. ora file to enable load balancing at client level. We can use following tnsnames. ora entry to enable client level load balancing.
What is the purpose of scan listener in oracle 11gr2?
SCAN Listener is the oracle component which starts running a service on the port (by default it’s 1521) using the SCAN VIP (IP address). So SCAN listener doesn’t start if SCAN VIP is not online. This is the major difference between a SCAN listener and SCAN VIP.
What are the four main daemons in RAC?
This includes start, stop, monitor, and failover operations. The crsd process generates events when the status of a resource changes.