Oracle DBA - DATABASE

Warning: long redo log write elapsed times detected, the LG* process tracefiles have more details This warning means LGWR / LGnn background processes are taking too long to write redo to the online redo logs. It is usually related to one of these: - Slow storage / high I/O latency on redo log disks - Redo logs placed on busy disks together with datafiles, FRA, archive logs, backups, or OS files - Too many commits from the application, causing frequent LGWR flushes - Redo log size too small, causing frequent log switches - CPU scheduling issue, where LGWR is not getting CPU quickly - Data Guard synchronous transport delay, if using SYNC/AFFIRM - In newer 19c RU versions, especially around 19.28, this warning can appear more visibly because of diagnostic changes, so first confirm whether there is a real performance impact before changing anything. - Oracle’s own wait-event documentation says log file sync is the foreground wait for redo write confirmation after commit, and log file paral...

 C:\iperf3.5_64>iperf3 -c 172.168.1.100 warning: Ignoring nonsense TCP MSS -13312 Connecting to host 172.168.1.100, port 5201 [  5] local 192.168.8.101 port 52570 connected to 172.168.1.100 port 5201 [ ID] Interval           Transfer     Bitrate [  5]   0.00-1.00   sec  6.88 MBytes  57.5 Mbits/sec [  5]   1.00-2.00   sec  3.50 MBytes  29.4 Mbits/sec [  5]   2.00-3.00   sec  4.00 MBytes  33.5 Mbits/sec [  5]   3.00-4.01   sec  6.25 MBytes  52.0 Mbits/sec [  5]   4.01-5.00   sec  4.75 MBytes  40.2 Mbits/sec [  5]   5.00-6.01   sec  5.50 MBytes  45.9 Mbits/sec [  5]   6.01-7.01   sec  5.88 MBytes  49.1 Mbits/sec [  5]   7.01-8.00   sec  5.25 MBytes  44....

VPD Policy Implementation - ORACLE Database  VPD policies Oracle CREATE TEST USERS in DB -- Owner schema for objects CREATE USER app_owner IDENTIFIED BY AppOwner#123 DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp QUOTA UNLIMITED ON users; GRANT CREATE SESSION, CREATE TABLE, CREATE PROCEDURE, CREATE ANY CONTEXT TO app_owner; -- Test application user CREATE USER app_user IDENTIFIED BY AppUser#123 DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp; GRANT CREATE SESSION TO app_user; CONNECT TO USER CONN app_owner/AppOwner#123  CREATE THE SAMPLE TABLE AND DATA CREATE TABLE employees (     emp_id         NUMBER PRIMARY KEY,     emp_name       VARCHAR2(100),     department_id  NUMBER,     salary         NUMBER ); INSERT TEST DATA   INSERT INTO employees VALUES (1, 'John',  10, 1000); INSERT INTO employees VALUES (2, 'Mary',  20, 1200); INSERT INTO empl...

Check current directory pathes which are on the source database. SELECT directory_name, directory_path FROM dba_directories; create and grant permision to run expdp for the same location which you want to run the backup. CREATE OR REPLACE DIRECTORY DUMP_NEW_DIR AS '/BACKUP'; GRANT READ, WRITE ON DIRECTORY DUMP_NEW_DIR TO SYSTEM; before running the below command create a file in the directory and give permissions as follows, chmod -R 777 export.par vi export.par  DIRECTORY=DUMP_NEW_DIR DUMPFILE=full_db_export_%U.dmp LOGFILE=export.log FULL=Y PARALLEL=2 run the command nohup to run this expdp without enteruptions. nohup expdp system/oracle123 parfile=export.par & check if any exp process are running on the database using below sql command. col owner_name format a12 col job_name format a25 col state format a15 col operation format a10 col job_mode format a12 select owner_name,        job_name,        operation,        job...