Database Reference
In-Depth Information
$ strings spfile+ASM1.ora|grep -v cluster > pfile+ASM1.ora
$ env ORACLE_SID=+ASM1 sqlplus / as sysdba
SQL> STARTUP NOMOUNT PFILE=pfile+ASM1.ora
ORA-29701: unable to connect to Cluster Manager
No progress here. This is because ASM instances depend on the Oracle Cluster Synchroni-
zation Service Daemon (OCSSD) of Oracle Clusterware for communication with RDBMS
instances.
Conversion of a CRS Installation to Local-Only
ASM does not require the full CRS stack. A stripped down version of CRS, which runs no
daemons except OCSSD, is sufficient. OCSSD implements the Cluster Synchronization Service,
which monitors node health through third-party cluster software, or in its absence makes its
own determination. It also provides notifications to ORACLE instances about cluster member-
ship and notifies CRSD and EVMD of the health of the cluster. The latter two daemons are not
mandatory for ASM instance operations.
A local-only installation of CRS does not require any voting disks. After all, there is just a
single node that could cast a vote. A file system file is used as the Oracle Cluster Registry (OCR),
so raw devices are not needed at all. The conversion consists of backing up the OCR as well as
other configuration files and running a few shell scripts located in
$ORA_CRS_HOME/install
and
$ORA_CRS_HOME/bin
.
A CRS installation for RAC is marked by three entries in
/etc/inittab
, as shown here:
$ grep '^h' /etc/inittab
h1:35:respawn:/etc/init.d/init.evmd run >/dev/null 2>&1 </dev/null
h2:35:respawn:/etc/init.d/init.cssd fatal >/dev/null 2>&1 </dev/null
h3:35:respawn:/etc/init.d/init.crsd run >/dev/null 2>&1 </dev/null
The parameter
local_only
in
/etc/ocr.loc
5
has the value FALSE.
$ cat /etc/oracle/ocr.loc
ocrconfig_loc=/opt/oracle/ocr
local_only=FALSE
A local-only CRS installation has but one entry in
/etc/inittab
and the parameter
local_only
is set to
TRUE
. Other differences in the directory structure below
/etc/oracle/
scls_scr
exist. We will first back up the current configuration of CRS. This involves taking a
backup of the cluster registry with
dd
, backing up configuration files and shell scripts, and
preserving the entries for CRS in
/etc/inittab
. These steps need to be performed as root:
# dd if=/opt/oracle/ocr bs=1048576 of=ocr.bin
258+1 records in
258+1 records out
# ocrdump ocr.txt
tar cvfP crs_local_only_false.tar /etc/oracle /etc/init.d/init.crs \
/etc/init.d/init.crsd /etc/init.d/init.cssd /etc/init.d/init.evmd \
The file
ocr.loc
is located in
/
var/opt/oracle
on some platforms.
5.
