Oracle 12c relink resets oracle group to oinstall, while 19c sets asmadmin

Problem:

In a mixed environment when you have 19c GI, but several versions of Oracle RDBMS home (19c, 12c), initially during 12c database restore you may encounter the following error:

ORA-15001: diskgroup "DATA" does not exist or is not mounted
ORA-15040: diskgroup is incomplete

There are several reasons for the above error and one of them is when the $ORACLE_HOME/bin/oracle binary under rdbms home does not have group asmadmin. After identifying it, you try to change permissions to oracle:asmadmin and but after a while, you may notice that the group is reset to oinstall. It can happen after patching or after running relink manually. So let’s see test case:

[oracle@rac1 lib]$ ll /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle
-rwsr-s--x 1 oracle asmadmin 323613256 Feb 19 17:00 /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle

Run relink:

[oracle@rac1 lib]$ make -f ins_rdbms.mk ioracle

Check permissions again:

[oracle@rac1 lib]$ ll /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle
-rwsr-s--x 1 oracle oinstall 323613256 Feb 19 17:03 /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle

If you do the same for 19c home, group is still asmadmin.

Reason:

ins_rdbms.mk script is different in 19c and 12c, comparing ioracle section:

12c:

ioracle: preinstall $(ORACLE)
        -$(NOT_EXIST) $(ORACLE_HOME)/bin/oracle ||\
           mv -f $(ORACLE_HOME)/bin/oracle $(ORACLE_HOME)/bin/oracleO
        -mv $(ORACLE_HOME)/rdbms/lib/oracle $(ORACLE_HOME)/bin/oracle
        -chmod 6751 $(ORACLE_HOME)/bin/oracle

19c:

ioracle: preinstall $(ORACLE)
        -$(RMF) $(ORACLE_HOME)/bin/oracle
        -mv $(ORACLE_HOME)/rdbms/lib/oracle $(ORACLE_HOME)/bin/oracle
        -chmod 6751 $(ORACLE_HOME)/bin/oracle

        -(if [ ! -f $(ORACLE_HOME)/bin/crsd.bin ]; then \
            getcrshome="$(ORACLE_HOME)/srvm/admin/getcrshome" ; \
            if [ -f "$$getcrshome" ]; then \
                crshome="`$$getcrshome`"; \
                if [ -n "$$crshome" ]; then \
                    if [ $$crshome != $(ORACLE_HOME) ]; then \
                        oracle="$(ORACLE_HOME)/bin/oracle"; \
                        $$crshome/bin/setasmgidwrap oracle_binary_path=$$oracle; \
                    fi \
                fi \
            fi \
        fi\
        );

As you see ioracle section in 12c does not contain the last IF statement which sets oracle binary group to asmadmin (using setasmgidwrap)

Solution:

Unfortunately, I cannot recommend adding that if statement in 12c ins_rdbms.mk although I did it in my test environment and works as expected.
After running make -f ins_rdbms.mk ioracle for 12c the group is set to asmadmin.

It is better to ask Oracle about this change and do only after you get an approval from them.

The only non-harmful recommendation from my side would be to have permission change script and run after every patch or relink:

# chown oracle:asmadmin  /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle
‚Äč# chmod 6751  /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle
# ll   /u01/app/oracle/product/12.1.0/dbhome_1/bin/oracle

If you still decide to add IF statement as I did, please make sure there is TAB instead of spaces before IF clause. Otherwise, you will get the following error and you can easily understand which line should be corrected.

[oracle@rac1 lib]$ make -f ins_rdbms.mk ioracle
ins_rdbms.mk:120: *** missing separator (did you mean TAB instead of 8 spaces?).  Stop.

RMAN restore on ASM fails ORA-12547: TNS:lost contact, WARNING: ASMB0 exiting with error

Problem:

Our client was not able to restore controlfile on +FRA diskgroup:

RMAN> restore controlfile to '+FRA' from '<backup file location>';
....
RMAN-03002 failure of restore command at 2021/05/24 19:12:19
ORA-19870: error while restoring backup piece 
ORA-19504: failed to create file '+FRA'
ORA-17502: ksfdcre:4 Failed to create file +FRA
ORA-15001: diskgroup "FRA" does not exist or is not mounted
ORA-12547: TNS:lost contact
ORA-12547: TNS:lost contact

Reason:

oracle binary under GI home did not have correct permissions:

[grid@rac1 bin]$ ll oracle
-rwxr-x--x 1 grid oinstall 420332360 Oct 13  2020 oracle

Solution:

Change permissions to 6751 and retry the restore:

[grid@rac1 bin]$ chmod 6751 oracle

[grid@rac1 bin]$ ll oracle
-rwsr-s--x 1 grid oinstall 420332360 Oct 13  2020 oracle