Thursday, May 28, 2009

OEM dbconsole Start Failed

Problem The dbconsole was working fine before the timezone setting (DST) was changed, but after the timezone was changed it stopped working.

solution When OEM dbconsole is started the agent timezone setting is recorded in the emd.properties. Everytime you start the dbconsole it will check the current timezone setting with the value in the emd.properties. When the two values mismatch the dbconsole will not start. We have to update the setting for the agent timezone.

To update follow the steps given below.

Check the timezone setting in /etc/environment.
The setting for TZ must be one of the supported timezone setting listed in the ORACLE_HOME/sysman/admin/supportedtzs.lst file


$ export ORACLE_SID=gcprod1
$ emctl config agent updateTZ
The output could be a different setting from the TZ in /etc/environment.

$ emctl stop dbconsole

$ emctl config agent updateTZ

$ emctl start dbconsole

Thanks
Vinod D

Wednesday, May 6, 2009

Bugs in Temp segments in RAC

Bug 2934117 : ORA-1652:Can’t acquire free extents owned by other node.The scripts fail as a result of the error

Solution: Do not use default temporary tablespace for a RAC configuration.
Workaround
Step1: Create a small temporary tablespace def_temp.
Step2: Set it as default temporary tablespace.
Step3: Create other normal temporary tablespace temp.
Step4: For all users change the temporary tablespace to temp.
Step5: Shutdown immediate all instances.
Step6: Startup all instances
Step7: when new users are created set the temporary tablespace as temp.


Bug 2858082 : Even if the free extents are available, ORA-1652 occurs in Alert Log on RAC. The scripts do not fail but errors appear inside alert.log of RAC instances.

In this bug although scripts that need Temp tablespace space due to Sort Operations (order by, group by, join, etc) are successfull we may see this error message inside alert.log of RAC instances.

When a RAC instance fills its own sort pool of extents, instead of allocation new extents it may ask for free temp extents from the other RAC instances. During this operation the ORA-1652 may appear inside the alert.log although the operation has succeeded.

Solution: You may ignore this error.

Thanks

ORA-01652 (RAC)

ORA-01652 Unable to extend temp segment by XX in tablespace tbs.

In an RAC environment this error occurs in the following situation

Out of space in temporary tablespace.

SQL> select sum(free_blocks) from gv$sort_segment where tablespace_name = '';

If the query returns 0 then increase the size of the tablespace.

Error occurs even though space is available in the tablespace

This situation occurs when we are requesting the sort segments from another instance. This should be considered as a warning to the DBA that there is instance contention for temporary tablespace.

Use the following query to monitor the instance wise temp space usage.

SQL> select inst_id, tablespace_name, total_blocks, used_blocks, free_blocks from gv$sort_segment;

Unlike non RAC environment, where the statement fails when this error occurs, the sort operations in RAC is successful.

Thanks

ORA-01652 (Non RAC)

ORA-01652 Unable to extend temp segment by XX in tablespace tbs.

The space in the temporary tablespace is not enough to allocate for the temp segment.

A temp segment, in the temporary tablespace, is not always used for sorting. It is sometimes used for creating objects such as index, CTAS etc. At the end of the creation these temp segments are converted in to the real objects. Hence rebuilding/creating a large index requires large temp segments thereby resulting in ORA-01652.

Solution: Increase the size of the temp tablespace by using the statement

SQL> Alter tablespace add tempfile ‘path’ size ‘size’;

Thanks

Followers

Powered By Blogger
 

Oracle Database Administration. Copyright 2008 All Rights Reserved Revolution Two Church theme by Brian Gardner Converted into Blogger Template by Bloganol dot com