Grid DBA

Since setting up our 10g RAC we have been experiencing problems connecting to the database via SQL*Plus. It would seem to work randomly and when it failed we got the error message ORA-12545 Connect failed because target host or object does not exist The following lines were added to the tnsnames.ora file: ORCL_TAF = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = orcl-rac1-vip)(PORT = 1521)) (ADDRESS = (PROTOCOL = TCP)(HOST = orcl-rac2-vip)(PORT = 1521)) (LOAD_BALANCE =yes) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = ORCL_taf) (FAILOVER_MODE = (TYPE = SELECT) (METHOD = BASIC) (RETRIES = 180) (DELAY = 5) ) ) ) LISTENERS_ORCL = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = orcl-rac1-vip)(PORT = 1521)) (ADDRESS = (PROTOCOL = TCP)(HOST = orcl-rac2-vip)(PORT = 1521)) ) ORCL2 = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = orcl-rac2-vip)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATE...

Our 2 node 10g RAC database would not startup after being shut down. The database was generating an error after trying to startup with command srvctl start database -d db1 It turns out that one of the other DBAs modified some database parameters sga_target to 1710 and forgot to add the M or convert it to bytes...ouch! Somehow one of the nodes got unregistered from the cluster. Soln: The following command was used to add back the instance to the cluster srvctl add instance -d dbname -i instance_name -n nodename