Veritas/Symantec DMP

If you use DMP, you must select Uses third-party multipath software for the initiator, as shown in Figure 6-11.

Figure 6-11 Initiator setting when DMP is used

The Switchover Mode and Path Type depend on the actual services, as described in Table 6-6.

• Use Huawei Storage Interoperability Navigator to query the volume management and cluster software supported by DMP.
• If a LUN has been mapped to the host, you must restart the host for the configuration to take effect after you modify the initiator parameters. If the host is running services, stop the services and export the disk group before restarting the host. If you configure the initiator for the first time, restart is not needed.
• Versions earlier than DMP 7.1 do not support multi-controller ALUA.
• If you do not use the recommended configurations, DMP may fail to identify paths or process paths incorrectly.
• For the software supported by SF DMP 5.x, contact Huawei technical support engineers.
• DMP 7.1 and later versions do not support common ALUA. Special mode 1 is supported on OceanStor Dorado V3 V300R002C10SPH105 and later patch versions, OceanStor V5 V500R007C30SPH105 and later patch versions, OceanStor V5 V500R007C10SPH015 and later patch versions, OceanStor V3 V300R006C50SPH105 and later patch versions, OceanStor V3 V300R006C20SPH015 and later patch versions, OceanStor Dorado V3 V300R002C20, OceanStor V5 V500R007C50, and OceanStor V3 V300R006C60. For other earlier versions, set Switchover Mode to ALUA not used.
• When the storage system is connected to a host with DMP 7.x and you have selected Uses third-party multipath software for the storage initiator and set the switchover mode to a special mode, the maximum number of online ports (FC, FCoE, or Ethernet) supported by a single storage system or HyperMetro storage systems is limited because the default RTPG buffer of Veritas VxVM (DMP) is 255. For details, consult Huawei engineers for evaluation. If the number exceeds the limit, problems such as path identification errors may occur.
• For a dual-controller storage system, you cannot add controllers online or create HyperMetro online under the following conditions: The storage system is connected to a host using DMP multipathing software; the initiator settings on the storage system are Uses third-party multipath software and ALUA not used; and the A/A mode is disabled. Otherwise, host services may be interrupted. To check whether the A/A mode is enabled, run show tgt_switch storage_work_mode on OceanStor V3 or V5 storage systems, or show scsi_upgrade_config storage_work_mode on Dorado storage systems. The following is an example:

  developer:/>show scsi_upgrade_config storage_work_mode
  Switch Type : A/A Work Mode
  AA Switch   : Off

  In the command output, Off indicates that the A/A mode has been disabled. For a dual-controller storage system, if you want to add controllers online, enable the A/A mode by running change tgt_switch storage_work_mode switch=on on OceanStor V3 or V5, or change scsi_upgrade_config storage_work_mode aa_switch=on on Dorado storage systems.

• To change the LUN mapping on the storage system, including but not limited to changing the host LUN ID, changing the port online, and removing and adding a LUN, follow the instructions in How Can I Change LUN Mappings When Non-Huawei Multipathing Software Is Used? to correctly change the LUN mapping. Otherwise, services may be interrupted.

1. Run the vxddladm listsupport all | grep huawei command to verify the ASL installation. In the following example, the multipathing software has correctly identified XSG1.

   bash-3.2# vxddladm listsupport all | grep huawei 
   libvxhuawei.so      HUAWEI, HUASY       S5100, S5300, S5500, S5600, S6800E, S8000, S8000-I, VIS6000, S5500T, S5600T, S5800T, S6800T, S2600T, V1500, V1800, S2100, S2200T, S2300, S2300E, S2600, S3900-M100, S3900-M200, S3900-M300, S5900-M100, S5900-M200, S6900-M100, Dorado2100, Dorado2100 G2, Dorado5100, HVS85T, HVS88T, XSG1 
   bash-3.2# 

   If XSG1 does not exist, upgrade the VRTSaslapm ASL online to a version that supports Huawei storage. You can obtain the ASL installation package for Huawei storage from https://sort.veritas.com/asl. Install ASL by following instructions in the Readme file on the official download page.

2. Run the vxdisk list command to check the device name. A correct device name is in the huawei-xxx format. Then run the vxdisk list device name command and check whether the number of paths and path status are correct (consistent with the actual configuration). In the following example, there are eight paths to a LUN, which are hdisk4, hdisk5, hdisk6, hdisk7, hdisk10, hdisk11, hdisk12, and hdisk13. All paths are enabled. The type of four optimal paths is active/optimized, and that of four non-optimal paths is active/non-optimized.

   bash-3.2# vxdisk list 
   DEVICE          TYPE            DISK         GROUP        STATUS 
   huawei-xsg12_0 auto:cdsdisk    T00DG1       T00DG        online 
   sanboot_disk_0 auto:LVM        -            -            LVM 
   sanboot_disk_1 auto:LVM        -            -            LVM 
   sanboot_disk_2 auto:LVM        -            -            LVM 
   sanboot_disk_3 auto:LVM        -            -            LVM 
   bash-3.2# vxdisk list huawei-xsg12_0
   Device:    huawei-xsg12_0 
   devicetag: huawei-xsg12_0 
   type:      auto 
   hostid:    sanboot 
   disk:      name=T00DG1 id=1554913890.8.sanboot 
   group:     name=T00DG id=1554913945.10.sanboot 
   info:      format=cdsdisk,privoffset=256 
   flags:     online ready private autoconfig autoimport imported 
   pubpaths:  block=/dev/vx/dmp/huawei-xsg12_0 char=/dev/vx/rdmp/huawei-xsg12_0 
   guid:      {1894fca2-5bae-11e9-b15b-183b2c4835d0} 
   udid:      HUAWEI%5FXSG1%5F2100845b125f50bb%5F6845B121005F50BB00146F0900000001 
   site:      - 
   version:   3.1 
   iosize:    min=512 (bytes) max=512 (blocks) 
   public:    slice=0 offset=65792 len=10411776 disk_offset=0 
   private:   slice=0 offset=256 len=65536 disk_offset=0 
   update:    time=1556059236 seqno=0.8 
   ssb:       actual_seqno=0.0 
   headers:   0 240 
   configs:   count=1 len=48144 
   logs:      count=1 len=7296 
   Defined regions: 
    config   priv 000048-000239[000192]: copy=01 offset=000000 enabled 
    config   priv 000256-048207[047952]: copy=01 offset=000192 enabled 
    log      priv 048208-055503[007296]: copy=01 offset=000000 enabled 
    lockrgn  priv 055504-055647[000144]: part=00 offset=000000 
   Multipathing information: 
   numpaths:   8 
   hdisk13         state=enabled   type=active/optimized 
   hdisk10         state=enabled   type=active/optimized 
   hdisk11         state=enabled   type=active/non-optimized 
   hdisk12         state=enabled   type=active/non-optimized 
   hdisk6          state=enabled   type=active/non-optimized 
   hdisk5          state=enabled   type=active/non-optimized 
   hdisk7          state=enabled   type=active/optimized 
   hdisk4          state=enabled   type=active/optimized 
   bash-3.2#