Setting up multipathing
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You can configure multiple network paths between the host and storage system by setting up multipathing. SnapDrive for UNIX does support the use of aliases in multipath environments. You need to make sure that the proper alias name for the mapper devices is configured in the
After the host reboots, the multipath daemon should be running as shown in the following example:
root@lnx197-123 ~]# ps -ef | grep multipathd root 5713 1 0 22:44 ? 00:00:00 /sbin/multipathd root 5739 1783 0 22:44 pts/1 00:00:00 grep multipathd
If the multipath daemon is not running, ensure that you restart the daemon after the reboot. You can start the multipath daemon by running the following command:
[root@lnx197-123 ~]# chkconfig --level 345 multipathd on
The following table lists some of the SnapDrive operations which support the use of alias name in multipath environment. Operation Alias name support Device type
Snap Create and Restore (SFSR and VBSR) from primary on primary host
Cloning from primary or secondary
Restore to alternate
Restore from secondary
You do not have to set any values in the
/etc/multipath.conffile if you are using either Red Hat Enterprise Linux (RHEL) 6.4 or later or Oracle Linux 6.4 or later.
However, you must still maintain a dummy
/etc/multipath.conffile, which can either be empty or containing the blacklisted information and alias names, if required.
You do not have to maintain a
/etc/multipath.conffile if you are using SUSE Linux Enterprise Server (SLES) 11 SP3 or later.
However, you can have a
/etc/multipath.conffile to contain the blacklisting information and alias names, if required.
Replace the string
HITACHI_HUS103073FL3800_V3WTL7XAwith the output of the command
scsi_id -gus /block/<LD>, where
LDis the local block device name.
For some local block devices, the
scsi_idcommand might not return any strings. In that case, the local block device must be blacklisted by using devnode directive.
Increase the number of file descriptors that a process can open in the host by appending the following lines in the
soft nofile 4096 hard nofile 4096
Ensure that the Linux SG Driver is always loaded after the system reboot by entering the following command:
echo "modprobe sg" >> /etc/rc.local
Reboot the host to ensure that settings are active.
The lvm2-2.02.17-7.27.8 and the
filtersetting must be assigned as =
"r|/dev/cciss/.*|", "a/.*/"]in the
lvm.conffile in SLES10 SP2.