JP : Interview questions

First round

What will u do when the switchover hungs?
hw do u perform the switchover? what are the prechecks u do ?
how to setup the DG in max protection mode?
How many standby redo logs required?
Can we create standy redo log files with diff size? if create what is impact?
While adding datafile forgot to specify '+' symbol. what happens to primay & standby? hw do you resolve ?
Due to some reason had to perform failover. How to do reconfigure dataguard for the failed (old) primary?
Had to perform the flashback db on primary. What happens to the standby? Will it also flashed back?
Difference between logical block corruption and physical corruption?
How do you calculate the no of channels that we can configure (limitations) ? In one server 10 DB are there, out of those 2 are critical, how do you allocate channels?

11gR2 what is the new feature implemented in collecting statistics
What are the histograms ? use and Types of hostograms.
One query is runnin fine in dev, same query is taking long time in Prod. How to you analyze? what colud be the reasons
sql profiles
AWR report
ASSM ( Automatic segment space mgmt) ?
Have u ever used memory advisor?
How to find the which indx is eligible for rebuild?
Rolling patch. patch failed on second node in rolling fashion. what u ll do ?\
Import is hung(Impdp), hw do u monitor? wht memory component is required for Impdp? how do find the optimal value for the large_pool_size?
how do u monitor server load ? which tool ? ( OS watcher)\
hw to reduce(tune) the log file sync wait event?

What Oracle has introduced in 11g R2 at binary level to detect the VD & OCR when ASM is not up? ( KFED, KFOD)
cache fushion. which b/g process is responsible?
diff b/w 10g & 11g RAC..
hw the cluster starts in 11gR2 (steps)
what s node eviction? diff b/w 10g & 11g (node eviction).
when node evicts in RAC?
In 11gR2, when the node(server) will be reboot?
if I kill ossd deamon what happens?
I f I kill crsd deamon what happens to the cluster?
If we create Voting disk on external redudancy DG, how many copies of VDisks will be created?

second round

How do you investigate the node eviction? which are all the logs you request to check?
Trying to start the cluster, but nothing is coming up. (ps -ef|grep ora) no process is found. How do you investigate?
How do you find the location of your OCR file without ocrconfig (when is cluster is down)?
What is default location of the OLR?
How do you find the location of the OLR?
How do you find the inventory of the oracle for what are all the binaries got installed on the server?
What is the cssmisscount?
Got an alert for RMAN backup failed due to insufficient space on the tape. What will you do?
What is main difference in the node eviction concept from 10g to 11.2.0.4?
How do you find the primate IP(Interconnect) for cluster? ( apart from the /etc/hosts)
In RAC, how do you apply the opatch for oracle grid?
To apply patch do we need to stop the cluster?
When you(root) unlock the grid what happens? will is stops the cluster? How to lock it back?
What file is required to start the ohsd.bin deamon (high avilability stack) ?
How do find at what time the node got evicted? ( apart from "uptime cmd in lower than 11g version).
In AWR report, found "log file sync" wait event in top. how do you reduce(resolve)?
Will lgwr (b/g) invoke for commit?
Will lgwr invoke for every checkpoint?
what is dynamic remastering? which is responsible for dynamic remastering?
Node1 is master node. I am trying to take ocr backup manually using ocrconfig. Where the does the backup created?

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first round

Breifly explain about your past experience & what kind of environement that you have worked?
What are the new features of ORACLE 11gR2?
What is main difference between the 10g & 11g cluster?
How do you take backup of Voting Disk and OCR files?
What is for voting disk and which background process is responsible for write the info to Voting Disk?
What does OCR contains?
Explain about SCAN.
Have a RMAN full backup on sunday & incremental backup on monday 10:00 PM. My Database crashed at 11:30 PM on Monday. How do you recover?

Second round

Explain about your past experience as oracle DBA? What kind of setup you have & what platform?

High level steps to install the RAC ( 2 node).
How do you perform upgrade (high level steps like pre-checks & post-upgrade steps).
How do you check the version of the database and what are all the critical patchsets have been applied?
During the critical patching, at what step oracle will update the patch info in the database (in v$registry) ?
What are the critical scenario's you have faced in the dataguard env?
You got an alert for database locks. What is your action?
What is best way to install oracle binaries in hundrards of servers?
What is the use of local_listener & remote_listener ?
what is the purpose of the virtual IP (VIP) in RAC?
Some of the blocks corrupted in one of datafile. How do you recover the block corruption?
What is IO fencing?
How do you find which is master node? What are the responsibilties of master node?

JP