Automatic Stop of Database (dbshut) not working in OL 7 with systemd (文檔 ID 2229679.1)SSSq

Automatic Stop of Database (dbshut) not working in OL 7 with systemd (文檔 ID 2229679.1)

APPLIES TO:

Oracle Database - Enterprise Edition - Version 12.1.0.2 and later

Oracle Database Exadata Cloud Machine - Version N/A and later

Oracle Cloud Infrastructure - Database Service - Version N/A and later

Oracle Database Cloud Exadata Service - Version N/A and later

Oracle Database Exadata Express Cloud Service - Version N/A and later

Information in this document applies to any platform.

Linux x86-64

SYMPTOMS

On : 12.1.0.2 version, RDBMS

When attempting to stop DB during server shutdown the automatic shutdown script getting below error

cat /u01/app/oracle/product/12.1.0.2/dbhome_1/shutdown.log

Processing Database instance "XXXX1": log file /u01/app/oracle/product/12.1.0.2/dbhome_1/shutdown.log

Info: Database instance "XXXX" already down (PMON process not there).

Which indicate that PMON is forcefully being closed before the script is called.

This is the configuration used

cat  dbora.service

[Unit]

Description=The Oracle Database Service

After=network.target

[Service]

Type=forking

# Type=oneshot

RemainAfterExit=yes

KillMode=none

# Set this to something larger if it has an impact

TimeoutStopSec=0

ExecStart=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbora start

ExecStop=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbora stop

[Install]

# Puts wants directive for the other units in the relationship

WantedBy=default.target

systemctl enable dbora.service

systemctl daemon-reload

systemctl start dbora.service

CHANGES

CAUSE

Issue with the dbora script which is doing su to oracle owner process and systemd is not able to keep track of that process.

This is the sample dbora script

ORA_HOME=/u01/app/oracle/product/12.1.0.2/dbhome_1

ORA_OWNER=oracle

case "$1" in

'start')

# Start the Oracle databases:

# The following command assumes that the oracle login

# will not prompt the user for any values

# Remove "&" if you don't want startup as a background process.

su - $ORA_OWNER -c "$ORA_HOME/bin/dbstart $ORA_HOME"

touch /var/lock/subsys/dbora

;;

'stop')

# Stop the Oracle databases:

# The following command assumes that the oracle login

# will not prompt the user for any values

su - $ORA_OWNER -c "$ORA_HOME/bin/dbshut $ORA_HOME"

rm -f /var/lock/subsys/dbora

;;

esac

With this arrangement the systemd is losing control over the service and not stopping it in time. 

SOLUTION

The better option is to use dbstart and dbstop script directly under the directive with user and owner details

[Unit]

Description=The Oracle Database Service

After=network.target

[Service]

Type=forking

RemainAfterExit=yes

KillMode=none

TimeoutStopSec=5min

User=oracle                                      << Replace Oracle software owner details here 

Group=oinstall

ExecStart=$ORACLE_HOME/bin/dbstart $ORACLE_HOME &             ===> Please use absolute path here instead of the $ORACLE_HOME variable

ExecStop=$ORACLE_HOME/bin/dbshut $ORACLE_HOME                 ===> Please use absolute path here instead of the $ORACLE_HOME variable

Restart=no

[Install]

# Puts wants directive for the other units in the relationship

WantedBy=default.target

Then systemd has control about the services

# systemctl status dbora.service

● dbora.service - The Oracle Database Service

Loaded: loaded (/usr/lib/systemd/system/dbora.service; enabled; vendor preset: disabled)

Active: active (running) since Wed 2017-02-01 12:19:53 GMT; 22s ago

Process: 3905 ExecStop=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbshut /u01/app/oracle/product/12.1.0.2/dbhome_1 (code=exited, status=0/SUCCESS)

Process: 4043 ExecStart=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbstart /u01/app/oracle/product/12.1.0.2/dbhome_1 & (code=exited, status=0/SUCCESS)

CGroup: /system.slice/dbora.service

├─4051 /u01/app/oracle/product/12.1.0.2/dbhome_1/bin/tnslsnr LISTENER -inherit

├─4143 ora_pmon_XXXXX

<snip>

└─4477 ora_q003_XXXX

 Additional Following directives need to be considered

1) If someone accidentally runs dbshut/dbstart as root , next valid attempt will consistently fail with:

Apr 25 18:04:57 instance-20190425-12corig dbstart: touch: cannot touch ?/u01/app/oracle/product/12.2.0/dbhome_1/startup.log?: Permission denied

Apr 25 18:04:57 instance-20190425-12corig dbstart: chmod: changing permissions of ?/u01/app/oracle/product/12.2.0/dbhome_1/startup.log?: Operation not permitted

Apr 25 18:04:57 instance-20190425-12corig dbstart: Processing Database instance "ORCL": log file /u01/app/oracle/product/12.2.0/dbhome_1/startup.log

to avoid, add these:

ExecStartPre=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/listener.log

ExecStartPre=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/startup.log

ExecStop=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/shutdown.log

2) To avoid such errors during a real reboot:

  Process: 4529 ExecStart=/u01/app/oracle/product/12.2.0/dbhome_1/bin/dbstart /u01/app/oracle/product/12.2.0/dbhome_1 (code=exited, status=203/EXEC)

  Apr 25 17:20:18 instance-20190425-12corig bash[4525]: /u01/app/oracle/product/12.2.0/dbhome_1: /u01/app/oracle/product/12.2.0/dbhome_1/bin/dbstart: No such file or directory

ADD 'local-fs.target' or 'remote-fs.target' (or both)

After=syslog.target network.target local-fs.target remote-fs.target

otherwise the FILESystem where $ORACLE_HOME lives is not ready, and dbstart cannot be found.

3) Add limit* settings as by design systemd does not honor /etc/security/limits.conf settings( Below are the optimal settings as per Database is concern, if you are using different setting at your system level please use those values instead) 

LimitNOFILE=65536

LimitNPROC=16384

LimitSTACK=32M

LimitMEMLOCK=infinity

LimitCORE=infinity

Example with all these together:

[Unit]

Description=Oracle Database Start/Stop Service

After=syslog.target network.target local-fs.target remote-fs.target

[Service]

# systemd, by design does not honor PAM limits

# See: https://bugzilla.redhat.com/show_bug.cgi?id=754285

LimitNOFILE=65536

LimitNPROC=16384

LimitSTACK=32M

LimitMEMLOCK=infinity

LimitCORE=infinity

Type=simple

User=oracle

Group=oinstall

Restart=no

ExecStartPre=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/listener.log

ExecStartPre=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/startup.log

ExecStart=/u01/app/oracle/product/12.2.0/dbhome_1/bin/dbstart /u01/app/oracle/product/12.2.0/dbhome_1

RemainAfterExit=yes

ExecStop=/bin/rm -rf  /u01/app/oracle/product/12.2.0/dbhome_1/shutdown.log

ExecStop=/u01/app/oracle/product/12.2.0/dbhome_1/bin/dbshut /u01/app/oracle/product/12.2.0/dbhome_1

TimeoutStopSec=5min

[Install]

WantedBy=multi-user.target