After system reboot logical volumes or file systems on the SAN are not accessible. How can I resolve

https://access.redhat.com/solutions/7225

 SOLUTION 已验证 - 已更新 2019年二月5日01:18 - 

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环境

• Red Hat Enterprise Linux
• Shared Storage (ISCSI, SAN)

问题

• Newly installed system with SAN devices attached fails to detect file system(s) at boot time. During reboot the logical volumes or file systems on the SAN are not accessible.
• During boot, system is not able to mount file systems and goes into single user mode forcing us to comment them on fstab due to some SAN devices not being present.

决议

• This problem is best solved by using the _netdev parameter in /etc/fstab for the device. It ensures that logical volumes are only activated and the file system mounted when the service netfs is started. Since this service is only started later in the boot process, it gives the SAN enough time to finish the process of presenting its LUNs.

• Add the _netdev parameter as a mount option in /etc/fstab for all affected file systems.  Note that this parameter should not be used for file systems needed for the operating system to successfully boot.  (Examples: /etc, /usr, /var.)

• For LVM file systems, change:

Raw

/dev/vgsan/lv01 /storage ext3 defaults 1 2

• Into:

Raw

/dev/vgsan/lv01 /storage ext3 _netdev 1 2

• For normal file systems, change

Raw

/dev/sda1 /storage ext3 defaults 1 2

• Into

Raw

/dev/sda1 /storage ext3 _netdev 1 2

• Start the netfs service :

Raw

[root@host ~]# service netfs start
[root@host ~]# chkconfig netfs on