Fibre Channel is designed to carry various command sets and their associated architectures over the same physical interface. Fibre Channel is primarily a transport medium, therefore, independent of the function that it is used for.
The TruCluster Software products use the Fibre Channel Protocol (FCP) for SCSI-3 to use Fibre Channel as the physical interface.
Fibre Channel, with its serial transmission method overcomes the limitations of parallel SCSI by providing:
Data rates of 12.5 MB/sec, 25 MB/sec, 50 MB/sec, 100 MB/sec, 200 MB/sec, and 400 MB/sec
Support for multiple protocols
Better scalability
Improved reliability, serviceability, and availability
Fibre Channel uses an extremely high transmit clock frequency to achieve the high data rate. Using optical fibre transmission lines allows the high-frequency information to be sent up to 10 Km, the maximum distance between transmitter and receiver.
Copper transmission lines may be used for shorter distances.
This section describes the basic Fibre Channel terminology:
All data is transferred in a packet of information called a frame. A frame is limited to 2112 bytes. If the information consists of more than 2112 bytes, it is divided up into multiple frames.
The source and destination of a frame. A node may be a computer system, redundant array of independent disks (RAID) array controller, or a disk device. Each node has a 64-bit unique node name (worldwide name) that is built into the node when it is built.
Each node must have at least one Fibre Channel port from which to send or receive data. This node port is called an N_Port. Each port has a 64-bit unique port name (worldwide name) that is built into the node when it is built.
A switch, or multiple interconnected switches, that route frames between the originator node (transmitter) and destination node (receiver). Fabrics do not originate nor are they the final recipient of frames; they pass frames on to the destination.
The ports within the fabric (fabric port). The port is called an F_port. Each F_port has a 64-bit unique port name (worldwide name) that is built into the node when it is built.
The physical connection between an N_Port and another N_Port or an N_Port and an F_Port. A link consists of two fibres, one to transmit information and one to receive information. The transmit fibre on one node is the receive fibre on the node at the other end of the link. A link may be optical fibre, coaxial cable, or shielded twisted pair.
Fibre Channel supports three different interconnect topologies:
Point-to-point (Section 6.2.1)
Fabric (Section 6.2.2)
Arbitrated loop (Section 6.2.3)
Note
It is possible to interconnect an arbitrated loop with fabric, creating a hybrid configuration. The fabric must have ports with loop capabilities (FL_Ports) to attach an arbitrated loop to the fabric. Hybrid configurations are not discussed in this document.
The point-to-point topology is the simplest of the Fibre Channel topologies. In a point-to-point topology, one N_Port is connected to another N_Port by a single link.
Frames require no routing; all frames transmitted by one N_Port are received by the other N_Port, and in the same order in which they were sent.
Figure 6-1 shows an example point-to-point topology.
The fabric topology provides more connectivity than point-to-point topology. The fabric topology allows up to 224 ports to be connected.
The fabric examines the destination address in the frame header and routes the frame to the destination node.
A fabric may consist of a single switch, or there may be several switches interconnected. Each switch contains two or more fabric ports (F_Port) that are interconnected by the fabric switching function, which routes the frame from one F_Port to another F_Port within the fabric.
When an N_Port is connected to a fabric F_Port, the fabric is responsible for the assignment of the Fibre Channel address to the N_Port attached to the fabric. The fabric is also responsible for selecting the route the frame will take, within the fabric, to be delivered to the destination.
When the fabric consists of multiple switches, the fabric may determine an alternate route to ensure that a frame gets delivered to its destination.
Figure 6-2 shows an example fabric topology.
In an arbitrated loop topology, frames are routed around a loop set up by the links between the nodes.
In the arbitrated loop topology, a node port is called an NL_Port (node loop port), and a fabric port is called an FL_Port (fabric loop port).
Figure 6-3 shows an example arbitrated loop topology.
The arbitrated loop topology is not supported by the TruCluster Software products.
Refer to the TruCluster Software Products Release Notes for Fibre Channel requirements and restrictions.
This section provides diagrams of some of the configurations supported by Tru64 UNIX and TruCluster Software Products Version 1.6.
Figure 6-4 shows a two-node Fibre Channel cluster with a single RA8000 or ESA12000 storage array with dual-redundant HSG80 controllers and a DSGGA Fibre Channel switch.
Figure 6-5 shows a cluster with a full complement of eight targets on one DSGGA Fibre Channel switch. Each member system represents one target, and each HSG80 represents one target.
Figure 6-6 shows a cluster configuration with two DSGGA Fibre Channel switches and two RA8000/ESA12000 storage arrays.
This section provides information about installing the Fibre Channel hardware needed for a TruCluster configuration accessing storage over the Fibre Channel.
For more information, see the following documentation:
PCI-to-Fibre Channel Host Adapter (KGPSA) User's Guide (AA-RF2JB-TE)
COMPAQ StorageWorks Fibre Channel Storage Switch Users Guide (AA-RHBYA-TE)
Compaq StorageWorks HSG80 Array Controller ACS Version 8.4 Configuration and CLI Reference Guide (EK-HSG84-RG)
Compaq StorageWorks HSG80 Array Controller ACS Version 8.4 Maintenance and Service Guide (EK-HSG84-SV)
Ensure that the member systems, the DSGGA Fibre Channel switch, and the HSG80 array controllers are placed within the lengths of the optical cables you will be using.
Note
The maximum length of the optical cable between the KGPSA and the DSGGA switch or switch and the HSG80 array controller is 500 meters short wave multi-mode fibre.
The DSGGA switch supports up to 8 (DS-DSGGA-AA) or 16 (DS-DSGGA-AB) full duplex 1.6025 Gb/sec ports. The ports can be connected to the KGPSA-BC PCI-to-Fibre Channel host adapter or an HSG80 array controller.
The switch has a front panel display and four push buttons that can be used to manage the switch. There are four menus that allow you to configure, operate, obtain status, or test the switch.
The DSGGA Switch also has a 10Base-T Ethernet (RJ45) port. You can use a telnet connection (or Web access) to manage the switch or obtain switch status. You have an expanded set of controls and displays using a telnet connection.
Note
You have to set the IP address and subnet mask from the front panel before you set up a telnet connection or gain Web access to the switch.
The DSGGA switch has slots to accommodate up to 4 (DS-DSGGA-AA) or 8 (DS-DSGGA-AB) plug-in interface modules. Each interface module in turn supports 2 gigabit (Gb) interface converter modules (GBIC). The GBIC module is the electrical-to-optical converter, and supports both 50 and 62.5 micron multi-mode fiber (MMF) using the standard SC connector. Only the 50 micron MMF optical cable is supported for the TruCluster Software Products.
If you need to install additional interface modules, do so before placing the switch in an inaccessible location. Remove the top cover to install the interface modules.
Ensure that you place the switch within 500 meters of the member systems (with KGPSA PCI-to-Fibre Channel adapter) and the HSG80 array controllers.
The DSGGA switch can be mounted in a 19-in (48.7 cm) rackmount installation or placed on a flat solid surface. The switch is shipped with adhesive rubber feet that you can install to prevent marring the surface.
When you plan the switch location, ensure that you provide access to the switch front. All cables plug into the front of the switch. Also, the control panel display and switches are on the front of the switch.
For an installation, at a minimum, you have to:
Place the switch or install it in the rackmount.
Connect the optical fiber cables.
Connect power to the switch.
Turn on the power. The switch runs a series of power-on self test (POST) tests.
Set the switch IP address, subnet mask (see Section 6.5.1.2.2), and switch name (see Section 6.5.1.2.4). The switch IP address and subnet mask must be set from the front panel. You must use a telnet session to set the switch name.
Reboot the switch (to enable the change in IP address and subnet mask to take effect).
For more installation information, see the COMPAQ StorageWorks Fibre Channel Storage Switch Users Guide.
If you want to manage the switch from a member system, you also need to connect the switch to the Ethernet with a 10Base-T cable and set the Ethernet IP address and subnet mask (see Section 6.5.1.2.2).
You can manage the DSGGA switch and obtain switch status from the front panel, by making a telnet connection, or by web access. The IP address and subnet mask have to be set before you can access the switch with a telnet session or through the web.
Before you can make a telnet connection or access the switch via the web, you must assign an IP address and subnet mask to the Ethernet connection using the front panel.
The DSGGA switch front panel consists of a display and four buttons. The display is normally not activated, but it is activated when any of the buttons are pressed. The display has a timer. After approximately 30 seconds of inactivity, the display will go out.
The four front panel buttons are:
Down--Downward triangle: Moves down the menu or decreases the value being displayed.
Up--Upward triangle: Moves up the menu or increases the value being displayed.
Note
When the up or down buttons are used to increase or decrease a numerical display, the number changes slowly at first, but changes to fast mode if the button is held down. The maximum number displayed is 255. An additional increment at a count of 255 resets the count to 0.
Tab/Esc--Leftward triangle: Allows you to tab through multiple optional functions, for example, the fields in an IP address. You can use this button to abort an entry, which takes you to the previous menu item. If pressed repeatedly, the front panel display will turn off.
Enter--Rightward triangle: Causes the switch to accept the input you have made and move to the next function.
Before you telnet to the switch, you must set the Ethernet IP address and subnet mask.
To use the front panel to set the Ethernet address and subnet mask, follow these steps:
Press any of the DSGGA switch front panel buttons to activate the display for the top-level menu. If Configuration Menu is not displayed, press the down button repeatedly until it is displayed:
Select Menu: Configuration Menu
Note
Pressing the down button selects the next lower top-level menu. The top-level menus are:
Configuration Menu Operation Menu Status Menu Test Menu
Press enter to display the first submenu item in the configuration menu, Ethernet IP address:
Ethernet IP address: 10.00.00.10 --
The underline cursor denotes the selected address field.
Use the up or down button to increase or decrease the displayed number. Use the Tab/Esc button to select the next field. Modify the address fields until you have the address set correctly.
Use the enter button to accept the value and step to the next submenu item (Ethernet Submask), and then repeat step 2 to set the Ethernet subnet mask.
Press the enter button to accept the Ethernet subnet mask.
Press the Tab/Esc button repeatedly to get back to the configuration menu in the main menu.
Note
After changing any configuration menu settings, you must reboot the switch for the change to take effect.
Press the down button to select the Operation Menu:
Select Menu: Operation Menu
Press the Enter button to display the first submenu in the Operation Menu:
Operation Menu: Switch Offline
Note
If the switch is operational, you must place the switch off line before rebooting or you will lose any transmission in progress.
Press the down button until the Reboot submenu item is displayed:
Operation Menu: Reboot
Press the Enter button. You are allowed to change your mind and not reboot:
Reboot Accept? Yes No
Use the Tab/Esc button to select
yes
to reboot
the switch.
Press the Enter button to reboot
the switch and execute the POST tests.
Refer to the COMPAQ StorageWorks Fibre Channel Storage Switch Users Guide for information on other switch configuration settings.
Before you telnet to the DSGGA switch, you must set the Ethernet IP address and subnet mask.
You can use a telnet session to log in to the switch with one of three user names:
other
user
admin
The default password for all the user names is
password.
You can set the user names and passwords by logging in as the
admin
user and executing the
passwd
command.
Enter a new user name (if desired)
and a new password for the user.
If you forget a password, you can reset the passwords (and user names) to the factory default from the front panel with the Configuration menu Reset to Default submenu item.
The three user names have different levels of privilege, as shown in the following list (in order of least privilege to highest privilege):
other--Are allowed to execute commands ending in
Show, such as
dateShow
and
portShow.
user--Can
execute all commands ending in
Show, plus any
commands from the help menu that do not change the state of the
switch, for example,
version
and
errDump.
admin--Provides access to all the commands that show up in
the help menu.
Most switch administration is done when logged in as
admin.
Notes
Use Ctrl-H to correct typing errors.
Use the
logoutcommand to log out from any telnet connection.There are three commands that can only be executed from a telnet session:
flashSet--Used to change a switch's configuration
flashShow--Displays the switch's configuration values
help--Displays the switch's common commands that can be executed from a telnet session
After you set the Ethernet address and subnet mask,
you can use a telnet session to log in to the switch to
complete other switch management functions or monitor switch status.
For example, if a systems'
/etc/hosts
file
contains an alias for the switches IP address, set the
switch name to the alias.
This allows you to telnet to the switch
name from that system.
Telnet from a system that has the IP address
in its
/etc/hosts
file and set the switch address
as follows:
# telnet 10.0.0.2
User admin
Passwd [Return]
:Admin> switchName fcsw1
:Admin> switchName [Return]
fcsw1
:Admin>
Note
When you telnet to the switch the next time, the prompt will include the switch name, for example:
fcsw1:Admin>
This section covers setting up the HSG80 controller for operation with Tru64 UNIX and the TruCluster products. For more information on installing the HSG80, see the Compaq StorageWorks HSG80 Array Controller ACS Version 8.4 Configuration and CLI Reference Guide.
To set up an HSG80 for TruCluster operation, follow these steps:
If not already installed, install the HSG80 controller(s) into the RA8000 or ESA1200 storage arrays.
Ensure that the external cache battery (ECB) is connected to the controller cache module(s). If an uninterruptible power supply (UPS) is used instead of the external cache battery, to prevent the controller from periodically checking the cache batteries after power is applied, enter the following command:
> set this CACHE_UPS
Note
Setting the controller variable
CACHE_UPSfor one controller sets it for both controllers.
Install the fibre optics cables between the switch and the HSG80.
Set the power verification and addressing (PVA) ID. Use PVA ID 0 for the enclosure that contains the HSG80 controller(s). Set the PVA ID to 2 and 3 on expansion enclosures (if present). Do not use PVA ID 1.
Remove the program card ESD cover and insert the controller's program card. Replace the ESD cover.
Connect a terminal to the maintenance port on one of the HSG80 controllers. You need a local connection to configure the controller for the first time. The maintenance port supports serial communication with the following default values:
9600 BPS
8 data bits
1 stop bit
No parity
Connect the RA8000 or ESA12000 to the power source and apply power.
From the maintenance terminal, use the
show
this
and
show other
commands to verify
that controllers have the current firmware version.
See the
Compaq StorageWorks HSG80 Array Controller ACS Version 8.4 Maintenance and Service Guide
for information on upgrading the firmware.
To ensure proper operation of the HSG80 with Tru64 UNIX and the TruCluster products, set the the controller values as follows:
set this scsi_version = scsi-2[1]set this nocommand_console_lun[2]set this port_1_profile = plda[3]set this port_1_topology = fabric[4]set this port_2_profile = plda[3]set this port_2_topology = fabric[4]set other scsi_version = scsi-2[1]set other nocommand_console_lun[2]set other port_1_profile = plda[3]set other port_1_topology = fabric[4]set other port_2_profile = plda[3]set other port_2_topology = fabric[4]set failover_copy = this_controller[5]
Specifies the host protocol to use. Also specifies how the Command Console LUN (CCL) is handled. When set to SCSI-2, the CCL is not fixed at a particular location, but floats depending on the configuration. For example, if D0 and D1 are defined on the controller (which map to LUN 0 and LUN 1), then the CCL device will appear at LUN 2. If D2 is then configured, the CCL device will appear at LUN 3. [Return to example]
Disables the virtual LUN used with the command console. [Return to example]
Defines the format used to present and interpret the LUN values
in the Fibre Channel command information set.
For the value of
plda, the LUN number ranges from 0 to 255, and is
contained in byte 1 of the 8-byte FCP_LUN field.
[Return to example]
Specifies fabric as the switch topology. [Return to example]
Specifies that the failover mode is transparent failover. With transparent failover, controller A (the upper controller) port 1 is active for units D0-D99. Controller A port 2 is passive for units D100-D199. Controller B port 1 is passive for units D0-D99 and active for units D100-D199. [Return to example]
Execute the
show connections
command to determine
the connection name, and then use the connection name to set the operating
system and unit offset.
In the following example, the connection name
is !NEWCON05.
The ! (explanation mark) is part of the name.
>show connectionsConnection Unit Name Operating System Controller Port Address Status Offset !NEWCON05 DIGITAL_UNIX THIS 1 000001 OL this 0 HOST_ID=1000-0000-C920-A6D9 ADAPTER_ID=1000-0000-C920-A6D9 >set !NEWCON05 unit_offset = 0[1] >set !NEWCON05 operating_system = digital_unix[2] >restart this[3] >restart other[4]
Set the relative offset for LUN numbering to 0. [Return to example]
Specify that the host environment connected to the Fibre Channel port is Tru64 UNIX. [Return to example]
Restart both controllers to cause all changes to take effect. [Return to example]
show this
and
show
other
commands to verify the changes.
Set up the storage sets as required for the applications to be used.
When you install the KGPSA PCI-to-Fibre Channel adapter module, you have to ensure that it is configured symmetrically. The following sections discuss KGPSA installation and configuration.
Use the following steps as a guide to installing the KGPSA PCI-to-Fibre Channel adapter module. See the PCI-to-Fibre Channel Host Adapter (KGPSA) User's Guide for more information.
Caution
Static electricity can damage modules and electronic components. Compaq recommends using a grounded antistatic wrist strap and a grounded work surface when handling modules.
If necessary, install the mounting bracket on the KGPSA module. Place the mounting bracket tabs on the component side of the board. Insert the screws from the solder side of the board.
The KGPSA should arrive with the gigabit link module (GLM) installed. If not, close the GLM ejector mechanism. Then, align the GLM alignment pins, alignment tabs, and connector pins with the holes, oval openings, and board socket. Press the GLM into place.
Install the KGPSA in an open 32- or 64-bit PCI slot.
Insert the optical cable SC connectors into the GLM. The SC connectors are keyed to prevent their being plugged in incorrectly. Do not use unnecessary force.
Connect the fiber optic cables to the DSGGA switch.
Ensure that each KGPSA adapter is configured into the system symmetrically.
If you are adding Fibre Channel hardware to an existing ASE
configuration, boot each member system to
single-user mode after all Fibre Channel hardware has been installed,
and the fibre optics cables are connected between the switch,
KGPSA adapters, and HSG80 RAID controller.
Run the
ase_fix_config
utility
to ensure that the
emx
(KGPSA) adapters are
configured symmetrically.
For more information on the
ase_fix_config
utility, see the TruCluster Software
Products
Software Installation
manual.
If this is an new installation and the software has not been
installed, install the Fibre Channel hardware.
When the TruCluster
software is installed, the
ase_fix_config
utility
is used to set up SCSI and fibre channel buses.
In order for the TruCluster Software Version 1.6 products to operate correctly, the SCSI and Fibre Channel adapters must be configured symmetrically.
The SCSI adapters have to be connected symmetrically, and the
KGPSA Fibre Channel adapters
(emxn) must also be
connected symmetrically.
All
emx0
adapters must
be connected to the same switch, and all
emx1
adapters must be connected to the same switch (which is not the same
switch that the
emx0
adapters are connected to).
See
Figure 6-6
for an example configuration.
The target ID to worldwide name mapping on each cluster member must to be symmetrically assigned.
For more information on the
emx
driver, see
emx(7).
After installing Fibre Channel hardware, the target ID to worldwide
name mapping is set up, on a first device encountered basis, the first
time the member system is booted.
The software does the mapping so you
do not have to take any action.
After the systems are operational, the
target ID mapping is written to the
emx
drivers
data and backup files,
/etc/emx.db
and
/etc/emx.db.bak.
The mapping is done on a first device encountered basis, so if
you boot all member systems, each system could have a different target
ID mapping and the contents of the
/etc/emx.db
and
/etc/emx.db.bak
files could be different
between systems.
To prevent this, the assignment of target ID mapping must
be synchronized.
To ensure that all cluster member systems have the same target ID mapping at initial boot, follow these steps:
Boot one member system to multi-user mode.
The initial target ID
mapping takes place, and is written to the
emx
drivers data and backup files,
/etc/emx.db
and
/etc/emx.db.bak.
Boot all other cluster member systems to single-user mode.
Copy the
/etc/emx.db
and
/etc/emx.db.bak
files from the first system
to each of the other systems to synchronize the target ID mapping.
Reboot each of the systems at single-user mode to multi-user mode.
Note
You can copy the
/etc/emx.dband/etc/emx.db.bakdatabase files in a TruCluster Software configuration because of the requirement for a symmetrical hardware configuration.
The target ID mapping does not change as long as there are no target ID changes or KGPSA adapters replaced. The only time you have to change the target ID to worldwide name mapping is if you add or replace a KGPSA adapter or modify target ID mapping.
Before covering the procedure to modify target ID mapping, you need to
know about the files used.
For more information on managing target ID
mapping and the files used, see
emx_data.c(4).
You need to rebuild the kernel after a KGPSA adapter is added or
replaced, or if changes are made to target ID assignments.
During the
kernel build, the
/sys/data/emx_data.c
file is
compiled to place the target ID to worldwide name mapping in the
kernel.
After booting the new kernel, The updated mapping values are
written out to the
emx
driver data files
(/etc/emx.db
and
/etc/emx.db.bak).
The
/sys/data/emx_data.c
file contains
EMX_FCPID_RECORD
entries.
Each record provides the mapping
for one target on one
emx
adapter.
The file format
is:
/*emx? tgtid FC Port Name FC Node Name */
{ 0, 0, 0x0050, 0xe11f, 0x0000, 0x310d, 0x0050, 0xe11f, 0x0000, 0x300d },
{ 0, 1, 0x0050, 0xe11f, 0x0000, 0x320d, 0x0050, 0xe11f, 0x0000, 0x300d },
{ 0, 5, 0x0010, 0x0000, 0x20c9, 0x25ca, 0x0010, 0x0000, 0x20c9, 0x25ca },
{ 0, 6, 0x0010, 0x0000, 0x20c9, 0x12ca, 0x0010, 0x0000, 0x20c9, 0x12ca },
{ 0, 7, 0x0010, 0x0000, 0x20c9, 0xfec9, 0x0010, 0x0000, 0x20c9, 0xfec9 },
{ 1, 0, 0x0050, 0xe11f, 0x0000, 0x310d, 0x0050, 0xe11f, 0x0000, 0x300d },
{ 1, 1, 0x0050, 0xe11f, 0x0000, 0x320d, 0x0050, 0xe11f, 0x0000, 0x300d },
{ 1, 5, 0x0010, 0x0000, 0x20c9, 0x28a6, 0x0010, 0x0000, 0x20c9, 0x28a6 },
{ 1, 6, 0x0010, 0x0000, 0x20c9, 0xaba6, 0x0010, 0x0000, 0x20c9, 0xaba6 },
{ 1, 7, 0x0010, 0x0000, 0x20c9, 0x63a7, 0x0010, 0x0000, 0x20c9, 0x63a7 },
The fields, from left to right are:
instance
(emx?)--Identifies the
emx
adapter.
The previous file contains entries for two
emx
adapters,
emx0
and
emx1.
cam_tgt_id
(tgtid)--The CAM target ID.
The
example shows target IDs of 0, 1, 5, 6, and 7 for
emx0
and
emx1.
port_name/node_name
(FC Port Name, FC Node
Name)--The Fibre Channel worldwide name identifying the device.
The worldwide name consists of a 64-bit port name and a 64-bit node
name.
Each of these 64-bit fields are broken up into 4
comma-separated 16-bit hexadecimal fields.
Note
If you compare the port and node names in the
/sys/data/emx_data.cfile with those reported by an HSG80 RAID array controller, you will find that the bytes are swapped in the 16-bit values of/sys/data/emx_data.c. For example, consider this worldwide name:0x0050, 0xe11f, 0x0000, 0x310d, 0x0050, 0xe11f, 0x0000, 0x300d
In
/sys/data/emx_data.c. This will be seen at the HSG80 as:5000-1fe1-0000-0d31-5000-1fe1-0000-0d30
Fortunately, you do not have to type the worldwide names into the
/sys/data/emx_data.c.
When the
emx
driver assigns target ID mappings, it writes a
text version of the mappings to the
/etc/emx.info
file.
The entries are formatted exactly as you would see them in the
/sys/data/emx_data.c
file, so you can cut and
paste from
/etc/emx.info
to
/sys/data/emx_data.c.
If you shut down an ASE configuration to modify the Fibre Channel
by adding or replacing a Fibre Channel device, the
target ID mapping has to be modified.
Because each device is assigned
a worldwide name when it is manufactured, if you replace the
emx0
adapter at target ID 6, because the new
adapter has a different worldwide name, it would not be seen.
To modify the target ID to worldwide name mappings after adding or replacing a fibre channel adapter, follow these steps:
Boot one member system to single-user mode.
Use an editor to cut and paste the target ID mapping
entry for the new device from
/etc/emx.info
to
/sys/data/emx_data.c.
Use the
doconfig
utility to generate a new
kernel.
The target IDs are compiled into the kernel from
/sys/data/emx_data.c, and later written by the
kernel to
/etc/emx.db
and
/etc/emx.db.bak.
During the compilation, each
EMX_FCPID_RECORD
in
the
/sys/data/emx_data.c
is checked as follows:
If the
cam_tgt_id
field matches an entry in the
existing target ID mappings for the named
emx
adapter, the existing target ID mapping is deleted.
If the device defined by the worldwide name already exists in the
target ID mapping for the defined
emx
adapter, the
existing entry is deleted.
If the
cam_tgt_id
is non-negative, the table entry is
added to the mapping.
Reboot the system to multi-user mode.
Boot all other member systems to single-user mode.
Copy the new
/etc/emx.db
and
/etc/emx.db.bak
files from the first system to all other
member systems.
Reboot the other member systems to multi-user mode.
After you create the new target ID to worldwide name mapping,
you can remove the mapping from the kernel if you want.
Create an
empty
/sys/data/emx_data.c
and rebuild the
kernel.
The kernel is cleared of target ID mappings, but the
/etc/emx.db
and
/etc/emx.db.bak
are not changed.
Any subsequent reboots use the on-disk database
files.