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Tuesday, October 28, 2014

Change your DG Protection Mode with one single parameter

Instead of setting 3 parameters to increase your detection and protection mode when using a DG environment, in 11g we can set just one parameter:

db_ultra_safe  = data_only, or data_and_index or off (Protect just table data, protect also index or none) .

This parameter changes these other 3 :  db_block_checking, db_lost_write_protect and db_block_checksum


Best Regards,
Paulo Portugal

Tuesday, October 14, 2014

Check if your database is using ASYNC_IO or not

TO check if your database is using async_io, just execute this query below;

SYS@ABR1 AS SYSDBA> select count(*) filetype_name,asynch_io from v$iostat_file group by filetype_name,asynch_io;

FILETYPE_NAME ASYNCH_IO
------------- ---------
   1 ASYNC_OFF
   1 ASYNC_OFF
   1 ASYNC_OFF
  15 ASYNC_ON
   1 ASYNC_OFF
   1 ASYNC_OFF
   1 ASYNC_OFF
   1 ASYNC_OFF
   1 ASYNC_OFF
   1 ASYNC_OFF
 185 ASYNC_ON
   1 ASYNC_OFF

12 rows selected.

SYS@ABR1 AS SYSDBA>


As you can see, I have 185 datafiles using ASYNC IO, if you cannot find anyone using ASYNC_ON, than you are not using ASYNC_IO, check your disk_asynch_io initialisation parameter and make sure it is set to TRUE.  Also check with your OS admin if your OS is ok to use ASYNC IO.

Best Regards,
Paulo Portugal


Thursday, October 2, 2014

GGSCI (host) 3> dblogin useridalias ggadm ERROR: Unable to open credential store. Error code 28761..

Add credentias to new version of GG:




GGSCI (host) 4> ADD CREDENTIALSTORE

Credential store created in ./dircrd/.

GGSCI (host) 5> ALTER CREDENTIALSTORE ADD USER ggadm, password xxxxx alias ggadm

Credential store in ./dircrd/ altered.

GGSCI (host) 6> dblogin useralias ggadm



This wors fine for me.

Best Regards,
Paulo Portugal