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Setting A/A array to Active/Standby in DMP

Level 6
Partner Accredited

I have an A/A array and one the controller has frequent intermittent errors, so I want to get the good controller as the primary and the faulty controller to standby until the controller is fixed.  I have looked at vxdmpadm commands and I am little confused by the options, so I have the following queries

  1. vxdmpadm setattr path <path-name> pathtype=<value> says you can set an individual disk path, to things like active, primary and standby, so this looks what I need so I set good controller to primary and faulty controller to standby but it seems this command can only be used for paths and not controller and I want to set it by controller - can I set this by controller?
  2. I cannot find an equivalent getattr for pathtype, so how do I see what the current value of pathtype is?
  3. vxdmpadm setattr enclosure <enclr-name> iopolicy=<value> says you can set by array, but it is unclear how this co-exists with pathtype.  It would seem that for pathtype=active, then the value of iopolicy is a subset as it defines how you load balance like minimumq or round-robin, but in "vxdmpadm setattr path <path-name> pathtype=<value>" section, only pathype=preferred mentions iopolicy which doesn't see to make sense as you could have path for disk on controller 1 as the preferred path using pathtype and then set the iopolicy to round-robin, so how do these 2 settings co-exist?
  4. vxdmpadm setattr enclosure <enclr-name> iopolicy=singleactive says
    "If configured for A/A arrays, there is no load balancing across the paths, and the alternate paths are only used to provide high availability (HA). If the current active path fails, I/O is switched to an alternate active path."
    This again sounds like what I want but is also says "No further configuration is possible as the single active path is selected by DMP" so this sounds like you can't specify which path is the "single active", and indeed, there seems to be no option to specify controller, so it is possible to specify which controller is active?
  5. If one of the answers to the above questions does not let me set one controllers as active and one as standby, how can I do this.




Level 6
Employee Accredited Certified

Hi Mike

Some answers below

1) No, those attributes are only available at the path level and not the enclosure level

2) Ty using the command below to display the path states

            vxdmpadm list dmpnode dmpnodename=<dmpnodename>


            vxdmpadm getsubpaths dmpnodename=<dmpnodename>

3) Round robin should only load balance on available active paths

4) My first thoughts are that singleactive will default to using the first path that is available. I would need to test further.