On 8/16/20 4:30 AM, McIntyre, Vincent (CASS, Marsfield) wrote:
Promise recommend the multibus option,
Promise docs are a bit messy. The multibus example is a mistake. There are only two options for this array: failover or group_by_prio. There are plenty of examples, for old distributions, at "Linux PerfectPath - Promise Multipath Driver", under: https://www.promise.com/Support/DownloadCenter/VTrak/Ex30/E830f#Utilities
Thanks for your analysis. The model is VTrak E830f (VTE830fD). The unit is definitely set to active-active controllers.
Yep, it's a dual controller array. But the controllers are no able to access to a LUN at the same time, and from all paths. Only high-end arrays(3PAR, Symmetrix, DS8000, ONTAP, VSP, ...) do this. In VTrak arrays, one LUN is owned only by one controller.
The firmware could use an update however, the latest release seems to have been overlooked. I'll try updating and look into enabling ALUA support.
If ALUA is not used, multipathd must be configured with the "failover" option for "path_grouping_policy"
One question about the man page though. it seems from the current text that putting hardware_handler "0" in the config would be ignored for arrays that are assumed to have ALUA support. However if the array has ALUA support turned off and multipathd detects this, then the package falls back to using hardware_handler "0" of its own accord? If that's correct, could that be added to the man page?
Debian 10 is using a very old multipath-tools release (0.7.9 - nov 2018) without any upstream fixes. I don't know if it's an old bug or the default setting "hardware_handler = 1 alua" was interfering. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
