The XenServer Host’s Settings

Multipath Configuration Settings

The 'Defaults' Section

Applies to all versions of XenServer

Add or modify the polling_interval as 10 (seconds)

defaults { polling_interval 10 }

This is a DataCore-required value that manages how often the Host checks for access on a previously detected as failed virtual disk path. A smaller setting will interfere with Host performance.

Do not add the 'polling_interval' parameter to the 'device' section as it will not work as expected.

The 'Device' Section

The following entries are all DataCore-required values. See the notes section following for more information.

With ALUA:

# XenServer 8.2

device {
vendor "DataCore"
product "Virtual Disk"
path_checker "tur"
path_grouping_policy group_by_prio
failback immediate
path_selector "round-robin 0"
prio alua
}

# XenServer 7.1/7.2

device {
vendor "DataCore"
product "Virtual Disk"
path_checker tur
failback 30
path_selector "round-robin 0"
rr_min_io_rq 100
# rr_min_io 100
path_grouping_policy group_by_prio
prio alua
}

Without ALUA:

# XenServer 8.2

device {
vendor "DataCore"
product "Virtual Disk"
path_checker "tur"
path_grouping_policy group_by_prio
failback immediate
path_selector "round-robin 0"
}

# XenServer 7.1/7.2

device {
vendor "DataCore"
product "Virtual Disk"
path_checker tur
failback 10
path_grouping_policy failover
prio hp_sw
}

  • vendor / product
    By default, all virtual disks created in SANsymphony will use the vendor and product strings ‘DataCore’ and ‘Virtual Disk’ listed above. Also see:
    Changing Virtual Disk Settings
  • failback
    For XenServer 7.1/7.2 an extra ‘wait’ period (10 seconds) was added to prevent unnecessary ‘failback’ attempts.
  • path_checker
    This is a DataCore-specific value. No other value should be used.
  • path_grouping_policy
    This is a DataCore-specific value. No other value should be used.
  • path_selector (applies to ALUA enabled Hosts only)
    This is a DataCore-specific value. No other value should be used.
  • prio
    For XenServer 7.1/7.2 the 'hp_sw' switch was required to get consistent failover/failback DataCore's own qualification tests.
  • rr_min_io_rq (applies to ALUA enabled Hosts only)
    Use on systems running kernels newer than 2.6.30. This is a DataCore-required value. No other value should be used.
  • rr_min_io (applies to ALUA enabled Hosts only)
    Use on systems running kernels older than 2.6.31.
    This is a DataCore-required value. No other value should be used.