10g&9i的alert日志：
进入oracle：
[zhangshengdong@oralocal1 ~]$ sudo su - oracle
[oracle@oralocal1 ~]$ sqlplus "/as sysdba"
SQL> select * from v$version; （查看一下版本）
SQL> show parameter dump;（查看一下dump）
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
background_core_dump string partial
background_dump_dest string /ora/OraHome/admin/oracle9i/bd
ump
core_dump_dest string /ora/OraHome/admin/oracle9i/cd
ump
max_dump_file_size string UNLIMITED
shadow_core_dump string partial
user_dump_dest string /ora/OraHome/admin/oracle9i/ud
ump
10g和9i的alert日志文件都在/ora/OraHome/admin/oracle9i/bdump中
[oracle@oralocal1 ~]$ cd /ora/OraHome/admin/oracle9i/bdump
[oracle@oralocal1 bdump]$ ls
alert_oracle9i.log
11g的alert日志发生了改变：
SQL> col name format a20;
SQL> col value format a40;
SQL> select name,value From v$diag_info;
NAME VALUE
-------------------- ----------------------------------------
Diag Enabled TRUE
ADR Base f:appzsd
ADR Home f:appzsddiag
dbmsoracle11goracle11
g
Diag Trace f:appzsddiag
dbmsoracle11goracle11
g race
Diag Alert f:appzsddiag
dbmsoracle11goracle11
galert
NAME VALUE
-------------------- ----------------------------------------
Diag Incident f:appzsddiag
dbmsoracle11goracle11
gincident
Diag Cdump f:appzsddiag
dbmsoracle11goracle11
gcdump
Health Monitor f:appzsddiag
dbmsoracle11goracle11
ghm
Default Trace File f:appzsddiag
dbmsoracle11goracle11
g raceoracle11g_ora_1864.trc
alert日志就在：
f:appzsddiag
dbmsoracle11goracle11g raceaalert_ora11g.log
f:appzsddiag
dbmsoracle11goracle11galertlog.xml
这两个文件中