alert.log File in 11g - New dump dest in 11g

In oracle 11g, alert file is saved in 2 location, one is in alert directory ( in XML format) and other in old style alert file in trace directory . Both contains the same information.

These logs are used when you are using the ADRCI . (Automatic Diagnostic Repository Command Interface)


Beginning with Release 11g, the alert log file is written as XML formatted and as a text file (like in previous releases). The default location of both these files is the new ADR home (Automatic Diagnostic Respository, yet another new dump dest in 11g).

The ADR is set by using the DIAGNOSTIC_DEST initialization parameter. If this parameter is omitted, then, the default location of ADR is, 'u01/oracle/product/ora11g/log' (depends on ORACLE_HOME settings).

The location of an ADR home is given by the following path, which starts at the ADR base directory: ADR_BASE/diag/product_type/product_id/instance_id

If environment variable ORACLE_BASE is not set, DIAGNOSTIC_DEST is set to ORACLE_HOME/log.

Within the ADR home directory are subdirectories:
alert - The XML formatted alertlog
trace - files and text alert.log file
cdump - core files

The XML formatted alert.log is named as 'log.xml'


eg:
/u01/app/oracle/diag/clients/user_oracle/host_1813406375_11/alert
log_998.xml



[oracle@gr host_1813406375_11]$ pwd
/u01/app/oracle/diag/clients/user_oracle/host_1813406375_11
[oracle@gr host_1813406375_11]$ ls
alert  cdump  incident  incpkg  lck  metadata  stage  sweep  trace