Linux system (in the case of Device Mapper)

Virtual Storage Platform One SDS Block Storage Administrator Guide

Version
1.17.x
Audience
anonymous
Part Number
MK-24VSP1SDS002-04

The following procedure allows the compute node to recognize whether the ALUA is enabled (specified on the storage side).

  1. Change the settings for the following items in /etc/multipath.conf:

    Item

    Setting value

    vendor "HITACHI"
    product "Hi-SDS*"
    path_grouping_policy group_by_prio
    prio alua
    detect_path_checker/ detect_checker 1 no
    path_checker 2 readsector0
    dev_loss_tmo See your distribution's documentation and set the maximum value.

    1. The parameter name differs depending on your distribution. See your distribution's documentation and set the appropriate parameter name.

    2. If a failure occurs in a storage node of VSP One SDS Block, when a value other than readsector0 is set, paths might be wrongly blocked. For this reason, verify that you set readsector0.

  2. Reload the alternate path daemon.
    # service multipathd reload

    No procedure is available for letting the compute node recognize an ALUA priority change set on the storage side. ALUA priority changes are recognized automatically.

    You can confirm the ALUA priority set on the storage side by running the following command.

    # multipath -ll

    Priority paths and non-priority paths are indicated as follows:

    Priority path: prio=50 status=active

    Non-priority path: prio=10 status=enable

    VSP One SDS Block does not support a mixed configuration of ALUA devices and non-ALUA devices.