Forceful startup of CRS, when minority VMs are down

If a minority of database nodes are down because of cloud maintenance, those nodes may not be startable. If CRS is also down on the remaining working nodes, manual intervention is required.

Before proceeding, confirm that the cluster still has majority quorum.

Majority formula = TRUNC((number of database nodes + number of quorum nodes) / 2) + 1

The cluster can only be started when the majority of voting members are available. If the majority of database nodes or quorum nodes are down, the steps below will not work.

Use the following procedure on each database node where CRS fails to start.

Procedure 1: Restart CRS cleanly

1. Temporarily disable CRS autostart

crsctl disable crs

2. Stop any running CRS processes

crsctl stop crs -f

It is normal to see errors such as CRS-4639 or CRS-4000 when running this command. You can continue with the next steps.

3. Kill any remaining ohasd.bin reboot processes

ps -ef | grep "ohasd.bin reboot" | grep -v grep | awk '{print $2}' | xargs kill -9 > /dev/null 2>&1

4. [Only if using FlashGrid cluster] Stop flashgrid_wait service

flashgrid-node stop-waiting

Expected output may look similar to this:

pkill -USR1 -f flashgrid_wait ... OK

5. Restart the ohasd services

systemctl restart ohasd
systemctl restart oracle-ohasd

6. Monitor CRS startup

First, check whether the Clusterware daemons are running:

crsctl status res -t -init

If the Clusterware daemons started successfully, check the cluster resources:

crsctl status res -t

If CRS does not start automatically, start it manually:

crsctl start crs -wait

If startup hangs on ora.storage, check the ASM alert log (alert_+ASM?.log).

Look for errors such as: ORA-15042, ORA-15040

If these errors are present, cancel the CRS startup, skip step 7, and continue with Procedure 2 below.

7. Re-enable CRS autostart

crsctl enable crs

Procedure 2: If CRS still does not start

Use this procedure if CRS did not start successfully and some CRS resources remain failed.

Repeat the following steps on each database node where CRS still fails to start.

1. Stop any running CRS processes

crsctl stop crs -f

2. Kill any remaining ohasd.bin reboot processes

ps -ef | grep "ohasd.bin reboot" | grep -v grep | awk '{print $2}' | xargs kill -9 > /dev/null 2>&1

3. Restart the ohasd services

systemctl restart ohasd
systemctl restart oracle-ohasd

4. Start only HAS

crsctl start has

5. Start ASM in nomount mode

Connect as the Grid Infrastructure owner, for example grid:

su - grid
sqlplus / as sysasm

Then start ASM in nomount mode:

startup nomount;

6. Try to mount all ASM diskgroups

alter diskgroup all mount;

7. If mounting all diskgroups fails, mount them one by one using force

For example:

alter diskgroup GRID mount force;
alter diskgroup DATA mount force;

Sometimes ASM delays background operations after an unclean shutdown. In that case, you may see a message similar to this in alert_+ASM?.log:

WARNING: Background operations delayed until 08/08/23 21:22:21 because ASM was not stopped cleanly and there could be disconnected client(s)

Do not cancel the running command. Wait until the time shown in the message. The diskgroup should mount after that delay.

8. Re-enable CRS autostart

crsctl enable crs

9. Check cluster status

crsctl status res -t