HP OpenVMS Systems Documentation

Two new System Management utility (SYSMAN) commands have been added. They are:

• IO FIND_WWID
  Probes all ports on the Fibre Channel and detects all previously undiscovered tapes and medium changers, and assigns a name to each. Displays a list of the devices and their assigned device names, and automatically records this information in the SYS$SYSTEM:SYS$DEVICES.DAT file. Also updates relevant local and clusterwide memory structures.
  Use this command prior to running the SYSMAN command IO AUTOCONFIGURE.
  Requires the CMKRNL privilege.
• IO REPLACE_WWID
  Updates appropriate file and memory data structures in case one tape drive must be physically replaced by another tape drive at the same FC LUN location.
  Requires the CMKRNL privilege.

The following DCL enhancements have been made:

• The SHOW DEVICE/FULL command now displays the WWID for Fibre Channel tape devices.
• The F$GETDVI lexical function now supports the new keyword WWID , which returns the Fibre Channel tape device's WWID.

This section lists the steps required to configure a new tape or medium changer on the Fibre Channel.

7.5.4.1 Basic Configuration Steps: Summary

The basic steps for configuring new Fibre Channel tape devices in a cluster are as follows:

1. Power on the new tape device(s).
2. Powercycle the MDR to update MDR mapping information.
3. Run SYSMAN to assign device names and configure the devices:

   $ MC SYSMAN SYSMAN> SET ENVIRONMENT/CLUSTER ! Execute on all nodes SYSMAN> IO FIND_WWID ! Assign names SYSMAN> IO AUTOCONFIGURE/LOG ! Configure devices SYSMAN> EXIT

You need to perform these steps only once for the initial configuration. After any subsequent system reboot, the devices will appear automatically.

7.5.4.2 Basic Configuration Steps: Details

Prior to configuring a tape device on Fibre Channel, the worldwide identifier (WWID) of the device must be detected and stored, along with a device name, in the text file SYS$SYSTEM:SYS$DEVICES.DAT. This is accomplished by using the new SYSMAN command IO FIND_WWID.

The IO FIND_WWID command probes all ports on the Fibre Channel and locates all tape and medium changer devices connected to an MDR. For tapes and medium changers that have not been detected by a previous IO FIND_WWID command, IO FIND_WWID assigns a device name, retrieves the WWID of the device, stores the device name and WWID data in the SYS$SYSTEM:SYS$DEVICES.DAT file, and updates memory structures.

Since the primary goal of IO FIND_WWID is to populate the SYS$DEVICES.DAT file, you need to invoke the IO FIND_WWID command only once for each device. IO FIND_WWID does not configure the $2$MGAnnnn: device for use by an application.

Once the information is stored in the file, subsequent use of the IO AUTOCONFIGURE command reads a memory-resident copy of the file and configures the tape and medium changer devices automatically, loading or connecting the device drivers as needed. The SYS$DEVICES.DAT file is read into memory during each system reboot; this action initiates the automatic configuration of tapes and medium changers on the Fibre Channel.

Note that running the IO FIND_WWID command for the first time detects all existing tape and medium changer devices on the system. If you add additional Fibre Channel tape devices to the system at a later time, you must first powercycle the MDR to update internal mapping information, and then run the IO FIND_WWID command again to append the new device information to the SYS$DEVICES.DAT file.

In an OpenVMS Cluster environment, various data structures in memory must be updated on each system when a new Fibre Channel tape device is added. To accomplish this, Compaq recommends that you run the SYSMAN IO FIND_WWID command on each Alpha node in the cluster. Alternatively, you can run IO FIND_WWID on one node, and then reboot the other nodes that share that same system disk, because the SYS$DEVICES.DAT file is read at boot time and causes memory structures to be correctly initialized.

In the case of multiple system disks in the cluster, ensure that all copies of the SYS$DEVICES.DAT file are kept consistent, preferably by running the IO FIND_WWID command on all nodes. Alternatively, you can run IO FIND_WWID to update just one SYS$DEVICES.DAT file, and then manually edit the remaining SYS$DEVICES.DAT files by cutting and pasting the appropriate device name and WWID records from the original file to the target files.

Compaq recommends that you refrain from copying the entire original file to another system disk. The SYS$DEVICES.DAT file is also used to define port allocation classes (PACs), and PAC entries could be transferred inadvertently to the target system.

Following is a configuration example using a TL891 tape library on a single node.

First, the SYSMAN command IO FIND_WWID displays a list of all previously undiscovered tape devices and their device names.

$ MCR SYSMAN IO FIND_WWID

%SYSMAN-I-OUTPUT, command execution on node SAMPLE
On port _SAMPLE$PGA0:, the following tape WWIDs and their proposed device
names have been found but not yet configured:

      [Device $2$GGA0]
      WWID=04100024:"DEC     TL800    (C) DEC3G9CCR82A017"

      [Device $2$MGA0]
      WWID=04100022:"DEC     TZ89     (C) DECCX939S2777"

      [Device $2$MGA1]
      WWID=04100022:"DEC     TZ89     (C) DECCX942S6295"

Note that the overall WWID consists of everything to the right of the equals sign. Each such WWID is unique; however, the header portion may not be unique, because the header reflects only the basic type and length of the the WWID data.

The IO FIND_WWID command automatically records the information about the new tape devices in SYS$SYSTEM:SYS$DEVICES.DAT:

$ TYPE SYS$SYSTEM:SYS$DEVICES.DAT
!
! Updated 23-OCT-2000 14:17:41.85:  DEC TL800
!
[Device $2$GGA0]
WWID=04100024:"DEC     TL800    (C) DEC3G9CCR82A017"
!
!
! Updated 23-OCT-2000 14:17:41.93:  DEC TZ89
!
[Device $2$MGA0]
WWID=04100022:"DEC     TZ89     (C) DECCX939S2777"
!
!
! Updated 23-OCT-2000 14:17:42.01:  DEC TZ89
!
[Device $2$MGA1]
WWID=04100022:"DEC     TZ89     (C) DECCX942S6295"
!

Next, the SYSMAN command IO AUTOCONFIGURE configures the tape device.

$ MCR SYSMAN IO AUTOCONFIGURE/LOG

%SYSMAN-I-OUTPUT, command execution on node SAMPLE
%IOGEN-I-PREFIX, searching for ICBM with prefix SYS$
%IOGEN-I-PREFIX, searching for ICBM with prefix DECW$
%IOGEN-I-SCSIPOLL, scanning for devices through SCSI port PKA0
%IOGEN-I-SCSIPOLL, scanning for devices through SCSI port PKB0
%IOGEN-I-FIBREPOLL, scanning for devices through FIBRE port PGA0
%IOGEN-I-CONFIGURED, configured device GGA0
%IOGEN-I-CONFIGURED, configured device MGA0
%IOGEN-I-CONFIGURED, configured device MGA1

Fianlly, the SHOW DEVICE/FULL command displays the WWID of the tape device.

$ SHOW DEVICE/FULL $2$MG

Magtape $2$MGA0: (SAMPLE), device type TZ89, is online, file-oriented device,
   available to cluster, error logging is enabled, controller supports
    compaction (compaction  disabled), device supports fastskip.

   Error count                    0    Operations completed                  0
   Owner process                 ""    Owner UIC                      [SYSTEM]
   Owner process ID        00000000    Dev Prot            S:RWPL,O:RWPL,G:R,W
   Reference count                0    Default buffer size                2048
   WWID   04100022:"DEC     TZ89     (C) DECCX939S2777"
   Density                  default    Format                        Normal-11
   Allocation class               2

   Volume status:  no-unload on dismount, position lost, odd parity.

Magtape $2$MGA1: (SAMPLE), device type TZ89, is online, file-oriented device,
  available to cluster, error logging is enabled, controller supports
    compaction (compaction  disabled), device supports fastskip.

   Error count                    0    Operations completed                  0
   Owner process                 ""    Owner UIC                      [SYSTEM]
   Owner process ID        00000000    Dev Prot            S:RWPL,O:RWPL,G:R,W
   Reference count                0    Default buffer size                2048
   WWID   04100022:"DEC     TZ89     (C) DECCX942S6295"
   Density                  default    Format                        Normal-11
   Allocation class               2

   Volume status:  no-unload on dismount, position lost, odd parity.

The F$GETDVI lexical function also retrieves the displayable WWID:

$ write sys$output f$getdvi("$2$MGA0","WWID")
04100022:"DEC     TZ89     (C) DECCX939S2777"

Once the device is named and configured, you can use the device in the same way that you use parallel SCSI tapes with DCL commands such as INITIALIZE, MOUNT, BACKUP, and COPY. Refer to the installation guide for individual tape layered products for details on product-specific support of Fibre Channel tapes.

Note that while medium changers on Fibre Channel are autoconfigured, the medium changers on parallel SCSI continue to require the IO CONNECT command to load the device driver. It is impossible to manually connect a Fibre Channel medium changer by the SYSMAN IO CONNECT command because the device name does not imply the device's physical location, as it does in parallel SCSI.

7.5.5 Changing the Name of an Existing Fibre Channel Tape Device

Because SYS$SYSTEM:SYS$DEVICES.DAT is a text file, you can edit it but only to change the unit number of a Fibre Channel tape or medium changer device. However, as stated earlier, Fibre Channel tape and medium changer device information is stored internally by OpenVMS using clusterwide data structures, specifically clusterwide logical names. In OpenVMS Version 7.3, the only supported way to clean up these data structures is to do a complete cluster shutdown. A rolling reboot (leaving at least one node up during the reboot of other nodes) is inadequate to clean up the structures.

The specific steps for changing an existing device name follow:

1. Edit the SYS$SYSTEM:SYS$DEVICES.DAT file to change the unit number of the chosen device. In the basic $2$MGAnnnn or $2$GGAnnnn format, only the nnnn portion can be edited. The maximum allowed value for nnnn is 9999 and must be decimal. Be sure to choose a unit number that is not already in use by another device for that device type.
   For example, if $2$MGA26 is already associated with the WWID of another tape, then choose a unit number other than 26; if $2$GGA4 is already associated with the WWID of another medium changer, then choose a unit number other than 4.
2. If there are multiple system disks in the cluster, edit each of the SYS$DEVICES.DAT files in the same way.
3. Shut down the entire cluster to clean up existing cluster data structures.
4. Reboot the cluster. The new device names will automatically appear.

To move a tape or medium changer device without changing its name, a cluster shutdown is not required. However, you must reboot each cluster node that will access the device so that the path information is updated in the unit control blocks that represent the device.

If a device is inadvertently moved to a new path without rebooting, then subsequent attempts to mount or initialize the device, or to issue a $QIO IO$_PACKACK to it will fail with a fatal drive error.

7.5.7 Serving a Fibre Channel Tape Device

In general, all OpenVMS Alpha Version 7.3 nodes in an OpenVMS Cluster have a direct path to Fibre Channel tape devices if the nodes are connected to the same Fibre Channel fabric as the MDR. VAX nodes and Alpha nodes running earlier versions of OpenVMS, as TMSCP clients, can be served Fibre Channel tape devices by an OpenVMS Alpha Version 7.3 node. To provide this feature, pre-Version 7.3 VAX nodes require the latest update kit for TUDRIVER.EXE, and pre-Version 7.3 Alpha nodes require the latest update kit for SYS$TUDRIVER.EXE.

Medium changers, whether connected to Fibre Channel or to parallel SCSI, cannot be TMSCP served.

7.5.8 Replacing a Fibre Channel Tape Device

If one tape drive must be physically replaced by another tape drive at the same FC LUN location within the MDR, update the appropriate data structures with the IO REPLACE_WWID command.

For example, you may need to replace a defective tape drive with a new drive without rebooting the cluster, and that drive may need to retain the device name of the previous tape at that location.

The replacement device should have the same SCSI target ID as the original device. Cease all activity on the device, then type the following command to update all the necessary file and memory data structures with the WWID of the new tape drive:

$ MCR SYSMAN IO REPLACE_WWID $2$MGA1

Execute this command on each Alpha node in the cluster environment. You can accomplish this with the following commands:

$ MCR SYSMAN
SYSMAN> SET ENVIRONMENT/CLUSTER
SYSMAN> IO REPLACE_WWID $2$MGA1

Given the name of a Fibre Channel tape device, it is helpful to know how to locate the Fibre Channel tape device. To do so, follow these steps:

1. From the system manager's account, run ANALYZE/SYSTEM.
2. At the SDA prompt, type CLUE SCSI/SUMMARY.
3. Search for the name of the device (for example, MGA3) in the column labeled DEVICE.
4. Note the corresponding value in the column labeled SCSI-LUN. This SCSI LUN value is the same value used by the MDR as the FC LUN. Also note the columns labeled Port and SCSI-ID for the device; all devices associated with that same port and SCSI-ID are attached to the same physical Fibre Channel port of the same MDR.
5. At the MDR console's AMC prompt, type ShowFcScsiMap . In the column labeled FC LUN, locate the value noted in step 4. Once you find the FC LUN value, note (on the same line) the corresponding values for SCSI Bus, SCSI Target ID, and SCSI LUN. This B:T:L information describes the physical location of the device within the MDR.

Fibre Channel tape devices can be configured in the context of booting from the Version 7.3 CDROM distribution kit. The configuration steps are the same as the steps described in Section 7.5.4. Specifically, you must use the SYSMAN IO FIND_WWID and IO AUTOCONFIGURATION commands to configure the tape devices prior to use.

The file, SYS$DEVICES.DAT, is not created in this environment; therefore all pertinent naming information is stored in the memory data structures. Each time the CDROM is booted, you must repeat the IO FIND_WWID and IO AUTOCONFIGURE commands to name and configure the tape devices.

Note that the name of a Fibre Channel tape device in the CDROM boot environment does not persist through reboots, and may differ from the name that is assigned when booting from a read/write system disk.

7.5.11 Using an MDR with Dual Fibre Ports

Currently each Fibre Channel port on an MDR supports up to eight devices. A dual Fibre Channel port module allows support for 16 devices (two sets of eight devices each). To achieve proper load balancing between the two ports of a dual-port module, refer to the MDR documentation for instructions on using Selective Storage Presentation (SSP) to assign a specific device to a specific MDR port.

Even if multiple paths exist (because of the presence of a dual Fibre port module, or even because of multiple KGPSA adapters in the host), only the first path detected during autoconfiguration is used. Therefore, it is important to issue the SSP load-balancing commands before issuing the SYSMAN command IO AUTOCONFIGURE. Also note that, when multiple paths exist to a Fibre Channel tape device, the SYSMAN command IO FIND_WWID will continue to detect and report the presence of the device on such extraneous paths, even though IO AUTOCONFIGURE will not subsequently configure or otherwise allow access to the device on those paths.

7.6 Using the AlphaServer Console for Configuring FC

The AlphaServer console can be used to view the status of an FC interconnect. This allows you to confirm that the interconnect is set up properly before booting. If you plan to use an FC disk device for booting or dumping, you must perform some additional steps to set up those FC disk devices at the console. These topics are discussed in the next sections.

7.6.1 Viewing the FC Configuration from the Console

Console SHOW commands can be used to display information about the devices that the console detected when it last probed the system's I/O adapters. Unlike other interconnects, however, FC disk devices are not automatically included in the SHOW DEVICE output. This is because FC devices are identified by their WWIDs, and WWIDs are too large to be included in the SHOW DEVICE output. Instead, the console provides a command for managing WWIDs, named the wwidmgr command. This command enables you to display information about FC devices and to define appropriate device names for the FC devices that will be used for booting and dumping.

Note the following points about using the wwidmgr command:

• To use the wwidmgr command, if your system is an AlphaServer model 8x00, 4x00, or 1200, you must first enter diagnostic mode. On all other platforms, the wwidmgr command can be issued at any time.
• The changes made by the wwidmgr command do not take effect until after the next system initialization. After using the wwidmgr command, you must issue the initialize command.

Refer to the Wwidmgr User's Manual for a complete description of the wwidmgr command.

The following examples, produced on an AlphaServer 4100 system, show some typical uses of the wwidmgr command. Other environments may require additional steps to be taken, and the output on other systems may vary slightly.

Note the following about Example 7-1:

• The wwidmgr -show wwid command displays a summary of the FC devices on the system. This command does not display information about device connectivity.
• There are two FC adapters and five disks. (All the disks are listed at the end, independent of the adapters to which they are connected.) In this example, each of the disks was assigned a device identifier at the HSG80 console. The console refers to this identifier as a user-assigned device identifier (UDID).

P00>>>set mode diag
Console is in diagnostic mode
P00>>>wwidmgr -show wwid
polling kgpsa0 (KGPSA-B) slot 2, bus 0 PCI, hose 1
kgpsaa0.0.0.2.1            PGA0        WWN 1000-0000-c920-a7db
polling kgpsa1 (KGPSA-B) slot 3, bus 0 PCI, hose 1
kgpsab0.0.0.3.1            PGB0        WWN 1000-0000-c920-a694
[0] UDID:10 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016 (ev:none)
[1] UDID:50 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026 (ev:none)
[2] UDID:51 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027 (ev:none)
[3] UDID:60 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021 (ev:none)
[4] UDID:61 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022 (ev:none)

Example 7-2 shows how the wwidmgr show wwid -full command displays information about FC devices and how they are connected. The display has two parts:

• The first part lists each path from an adapter to an FC port. Adapters are identified by console device names, such as KGPSAA. FC ports are identified by their WWID, such as 5000-1FE1-0000-0D14. If any FC disks are found on a path, they are listed after that path. FC disks are identified by their current console device name, followed by their WWID.
• The second part of the display lists all the FC disks and the paths through which they are reachable. In this part, which begins with [0] UDID:10... , you will see there are four paths to each disk with two paths through each adapter, KGPSAA and KGPSAB. Each path through an adapter goes to a different port on the HSG80. The column titled Con indicates whether the FC disk unit is currently online to the HSG80 controller that this path uses.

P00>>>wwidmgr -show wwid -full

kgpsaa0.0.0.2.1
- Port: 1000-0000-c920-a7db

kgpsaa0.0.0.2.1
- Port: 2007-0060-6900-075b

kgpsaa0.0.0.2.1
- Port: 20fc-0060-6900-075b

kgpsaa0.0.0.2.1
- Port: 5000-1fe1-0000-0d14
 - dga12274.13.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016
 - dga15346.13.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026
 - dga31539.13.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027
 - dga31155.13.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021
 - dga30963.13.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022

kgpsaa0.0.0.2.1
- Port: 5000-1fe1-0000-0d11
 - dga12274.14.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016
 - dga15346.14.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026
 - dga31539.14.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027
 - dga31155.14.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021
 - dga30963.14.0.2.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022

kgpsab0.0.0.3.1
- Port: 1000-0000-c920-a694

kgpsab0.0.0.3.1
- Port: 2007-0060-6900-09b8

kgpsab0.0.0.3.1
- Port: 20fc-0060-6900-09b8

kgpsab0.0.0.3.1
- Port: 5000-1fe1-0000-0d13
 - dgb12274.13.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016
 - dgb15346.13.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026
 - dgb31539.13.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027
 - dgb31155.13.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021
 - dgb30963.13.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022

kgpsab0.0.0.3.1
- Port: 5000-1fe1-0000-0d12
 - dgb12274.14.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016
 - dgb15346.14.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026
 - dgb31539.14.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027
 - dgb31155.14.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021
 - dgb30963.14.0.3.1 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022


[0] UDID:10 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0016 (ev:none)
 - current_unit:12274 current_col: 0 default_unit:12274
          via adapter       via fc_nport       Con     DID     Lun
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d14   Yes   210013     10
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d11   No    210213     10
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d13   Yes   210013     10
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d12   No    210213     10

[1] UDID:50 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0026 (ev:none)
 - current_unit:15346 current_col: 0 default_unit:15346
          via adapter       via fc_nport       Con     DID     Lun
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d14   Yes   210013     50
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d11   No    210213     50
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d13   Yes   210013     50
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d12   No    210213     50

[2] UDID:51 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0027 (ev:none)
 - current_unit:31539 current_col: 0 default_unit:31539
          via adapter       via fc_nport       Con     DID     Lun
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d14   Yes   210013     51
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d11   No    210213     51
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d13   Yes   210013     51
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d12   No    210213     51

[3] UDID:60 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0021 (ev:none)
 - current_unit:31155 current_col: 0 default_unit:31155
          via adapter       via fc_nport       Con     DID     Lun
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d14   Yes   210013     60
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d11   No    210213     60
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d13   Yes   210013     60
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d12   No    210213     60

[4] UDID:61 WWID:01000010:6000-1fe1-0000-0d10-0009-8090-0677-0022 (ev:none)
 - current_unit:30963 current_col: 0 default_unit:30963
          via adapter       via fc_nport       Con     DID     Lun
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d14   Yes   210013     61
 -      kgpsaa0.0.0.2.1  5000-1fe1-0000-0d11   No    210213     61
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d13   Yes   210013     61
 -      kgpsab0.0.0.3.1  5000-1fe1-0000-0d12   No    210213     61