Shulou(Shulou.com)06/01 Report--

RAC environment:

Oracle database: oracle11gr2

Operating system: rhel6.4_x86_64

Failure phenomenon:

1. Rac failed to start processes and instances related to asm in the oracle of one of its nodes

View method: ps-ef | grep ora_

Ps-ef | grep asm_

Crsctl stat res-t (only oracle instances and asm instances launched on node 1 can be seen)

2. The asm disk device label cannot be seen on node 2

Viewing method: oracleasm listdisks (no content)

Ll / dev/oracleasm/disks/* (no content)

3. Scan asm disk on Node 2 the following error

Viewing method: oracleasm scandisks

Reloading disk partitions: done

Cleaning any stale ASM disks...

Scanning system for ASM disks...

Instantiating disk "VOL4"

Unable to instantiate disk "VOL4"

Instantiating disk "VOL1"

Unable to instantiate disk "VOL1"

4. Check the oracleasm log information and prompt the permission question.

Viewing method: cat / var/log/oracleasm

Analysis process:

In order to eliminate the interference of other factors, I rebooted the operating system of node 2. After restarting, the asm disk on node 2 still could not be loaded normally. By looking at the oracleasm log, it is still suggested that it is a permission problem. Boldly guess that there may be the following reasons leading to asm

The disk does not load properly:

1. The installation of asm-related rpm packages is abnormal, such as the version does not correspond to each other.

2. Security services related to the operating system lead to

3. The rule rules are not configured correctly when the system is rebooted, so that the asm disk cannot be loaded normally.

Exclude:

1. Rpm-aq | grep oracleasm needs to install 3 packages (kmod-oracleasm oracleasmlib oracleasm-support)

2. Service iptables status (iptables service shuts down)

Getenforce (check the status enforcing, indicating that the selinux service is not turned off)

3. This example does not use raw bare devices, so no rule rules are configured to be loaded at startup.

Treatment method:

Since the selinux service of Node 2 is not turned off, shut down the selinux service

Setenforce 0

Vi / etc/sysconfig/selinux

Change SELINUX=enforcing to SELINUX=disabled so that restarting the server will not start the selinux service

After shutting down the selinux service, perform an asm disk scan operation to identify the asm disk normally.

Oracleasm scandisks

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