Redis user permissions (ACL) and python connection

-
 Recently, I was working on setting up a redis cluster along with separate users for readwrite and readonly. I setup the readonly user using the below privileges (ACLs):   user redisreadonly on >mySuperSecretPassword ~* resetchannels -@all +@read +ping +asking   Once this is setup, I wrote a simple program in python to connect to the redis cluster using the readonly credentials and print the number of keys.   #!/usr/bin/env python3 """ pip3 install redis """ from redis.cluster import RedisCluster, ClusterNode # ─────── Cluster connection ─────── startup_nodes = [ ClusterNode("redis_host_1", 6379), ClusterNode("redis_host_2", 6379), ClusterNode("redis_host_3", 6379) ] rc = RedisCluster(startup_nodes=startup_nodes,decode_responses=True,username='redisreadonly',password='mySuperSecretPassw...
Post a Comment

Extract Controlfile, Datafiles & Archivelogs from RMAN Backupsets

-
The other day, one of my colleagues posed me this interesting and thought-provoking question/scenario: "Suppose, you were to lose both your production and your RMAN catalog databases irrevertably. You do have a full/incremental RMAN backup, however. How are you going to recover?"


How indeed? I scratched my head and shone a torch upon the dark recesses of my memory to come up with an answer. The light (of the torch) did indeed reveal something - that is that a note existed in Metalink which list the method that could be used to delve into a RMAN backup set to extract the controlfile, the datafiles and also the archivelogs and Voilà, I hit the nail right on the head.


I did some more digging and found a bunch of "Notes" in Metalink that pointed me to the eventual answer to the above question. The Notes that I am referring to are listed below. A summary of the procedure to be followed in such scenarios is also provided. All the notes mentioned use the package dbms_backup_restore.


Scenario:


A successful production backup (RMAN) is available (cold or hot - if hot, then the archivelogs are also available) while the production and the RMAN catalog databases are irrevertably lost.



Assumptions:


1. RMAN is being used to backup the database.


2. The RMAN backup is a "good" backup and is restore and recovery ready.


3. The list of datafiles (file name + full file path) and their datafile numbers is available (this can be obtained from the RMAN backup log file).



Solution Summary (from Note ID: 388057.1):


1. Start the target instance (nomount).


2. Restore the latest controlfile, ideally from the same backupset as the last incremental to be restored (Note 388052.1 : restore controlfile using PLSQL).


3. Make further copies if necessary as per the target database init.ora (pfile).


4. Mount the target instance (alter database mount).


NOTE: (RMAN may be able to be used to restore / recover the database at this point if the controlfile restored knows about the backup required to be restored and recovered).

5. Restore the datafiles from the level 0 backupset (Note 388053.1 : restore datafiles using PLSQL).


6. Restore (apply) the datafiles from the incremental backupsets (Note 388054.1 : restore incremental backups using PLSQL).


7. Restore the archivelogs from the archivelog backupset (Note 388055.1 : restore archivelogs using PLSQL).


8. Using traditional recovery techniques, recover the database using SQLPLUS. (until cancel using backup controlfile).


9. Open the database (resetlogs).


10. Rebuild the recovery catalog & re-register the target database.


11. Make backups of the target database and recovery catalog database.


References:


1. 60545.1 - How to Extract Controlfiles, Datafiles, and Archived Logs from RMAN Backupsets


2. 388052.1 - How to Extract the Control file from an RMAN backupset using PL/SQL


3. 388053.1 - How to Extract Datafile(s) from an RMAN backupset Level-0(Full) backup using PL/SQL.


4. 388054.1 - How to Extract Incremental Backups of Datafile(s) from an RMAN Incremental backupset Level-1 or higher using PL/SQL.


5. 388055.1 - How to Extract archive logs from an RMAN using PL/SQL.


6. 388057.1 - How to Restore an RMAN Backed up database using PL/SQL.

Comments

Post a Comment

Popular posts from this blog

Interesting Oracle Applications (EBS) Interview Questions

-
Below are some interesting interview questions that I have faced over the years. What is the difference between a concurrent manager and a cron job? Can one patch a CRS Oracle home with the CRS services up? Suppose, there are 2 nodes node1 and node2 with CRS cluster and one wants to patch node1. Can it be done with node2 being up? Suppose one fires a select statement and the data does not in the library cache, then the data, obviously, has to be fetched from the data files. Which background process is used for this purpose? What are the sizing requirements for say, a 100 concurrent users Oracle Apps Installation? What is the difference between a shared appl_top and a staged appl_top?
Read more

Modify retention period of workflow queues

-
Yesterday, there was a requirement to increase the retention period of WF_DEFERRED and WF_BPEL_Q so that the developers could troubleshoot issues involving business events. This can be done this way: 1. Check the retention period of existing workqueues. SQL> SELECT owner, name, retention FROM all_queues WHERE name LIKE 'WF%'; OWNER           NAME                                                RETENTION --------------- --------------------------------------------- ------------------------------ APPS                 WF_BPEL_Q                                                0 APPLSYS         WF_INBOUND_QUEUE              ...
Read more

Check if UTL_FILE and FND_FILE are working fine

-
Yesterday, while troubleshooting a vexing ORA-29280 error, I came across 2 useful PL/SQL anonymous blocks that can be used to test FND_FILE and UTL_FILE to find out whether they are indeed working fine. UTL_FILE set serveroutput on DECLARE file_location VARCHAR2(256) := '<first entry on utl_file_dir>'; file_name VARCHAR2(256) := 'utlfile1.lst'; file_text VARCHAR2(256) := 'THIS IS A TEST'; file_id UTL_FILE.file_type; BEGIN file_id := UTL_FILE.fopen(file_Location, file_name, 'W'); UTL_FILE.put_line(file_id, file_text); UTL_FILE.fclose(file_id); EXCEPTION WHEN UTL_FILE.INVALID_PATH THEN dbms_output.put_line('Invalid path ' || SQLERRM); WHEN OTHERS THEN dbms_output.put_line('Others '|| SQLCODE || ' ' || SQLERRM); END; / References: Metalink (MOS) Note ID: 261693.1 FND_FILE set serveroutput on exec FND_FILE.PUT_LINE(FND_FILE.LOG, 'THIS IS A TEST'); HTH....
Read more