Important Log Locations for Grid Infrastructure

Clusterware daemon logs are all under <GRID_HOME>/log/<nodename>. Structure under <GRID_HOME>/log/<nodename>:

alert<NODENAME>.log - look here first for most clusterware issues
./admin:
./agent:
./agent/crsd:
./agent/crsd/oraagent_oracle:
./agent/crsd/ora_oc4j_type_oracle:
./agent/crsd/orarootagent_root:
./agent/ohasd:
./agent/ohasd/oraagent_oracle:
./agent/ohasd/oracssdagent_root:
./agent/ohasd/oracssdmonitor_root:
./agent/ohasd/orarootagent_root:
./client:
./crsd:
./cssd:
./ctssd:
./diskmon:
./evmd:
./gipcd:
./gnsd:
./gpnpd:
./mdnsd:
./ohasd:
./racg:
./racg/racgeut:
./racg/racgevtf:
./racg/racgmain:
./srvm:

The cfgtoollogs dir under <GRID_HOME> and $ORACLE_BASE contains other important logfiles. Specifically for rootcrs.pl and configuration assistants like ASMCA, etc...

ASM logs live under $ORACLE_BASE/diag/asm/+asm/<ASM Instance Name>/trace

The diagcollection.pl script under <GRID_HOME>/bin can be used to automatically collect important files for support. Run this as the root user.

基本上和10g的没有太多的差别，如果是安装的话，还需要看$GRID_HOME/cfgtools下的log，也挺有帮助的。