How to Resize the Oracle Redologs files

1. go to UNIX level , su to oraSID user adn login into sqlplus:

su - oraSID

sqlplus "/ as sysdba"

2. find names of redo logs and their groups:

SELECT a.group#, a.member, b.bytes FROM v$logfile a, v$log b WHERE a.group# = b.group# order by a.group# asc;

3. Make last redo log current:

select group#, status fromv$log;
alter system switch logfile;

4. Drop inactive redo log group:

alter database drop logfile group 1;

5. Recreate dropped redo log group:

SQL> alter database add logfile group 1 ('/oracle/SID/origlogA/log_g11m1.dbf','/oracle/SID/mirrlogA/log_g11m2.dbf') size 200m reuse;

6. Force log switch:

select group#, status from v$log;
alter system switch logfile;
select group#, status from v$log;

7. repeate steps 3-6 untill all redo logs are rebuild

8. check the new size of redologs