HP StorageWorks Using IBM AIX Native MPIO with HP Enterprise

HP StorageWorks
Using IBM AIX Native MPIO with HP
Enterprise Virtual Array storage systems
application notes
Part number: AA-RW7EC-TE
Second edition: August 2006
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About this document
This section describes the following topics:
•
•
•
•
Application notes information, page 3
Intended audience, page 3
Accessing future product updates, page 3
Other documentation, page 3
Application notes information
These application notes describe the following major topics:
•
•
•
•
•
•
•
•
•
•
MPIO overview, page 4
New features, page 4
Supported hardware and software, page 4
Preparing for installation, page 5
Installing the ODM fileset, page 5
Removing the ODM fileset, page 7
IBM AIX native commands, page 8
HP AIX MPIO utilities, page 9
Path health checking feature, page 10
Static LUN Based load balancing, page 10
Intended audience
This document is intended for customers who are using IBM AIX Native MPIO with an HP StorageWorks
4000/6000/8000 Enterprise Virtual Array (EVA4000/6000/8000) storage system.
Accessing future product updates
HP strongly recommends that customers sign up online using the Subscriber’s choice web site:
http://www.hp.com/go/e-updates.
Subscribing to this service provides you with e-mail updates on the latest product enhancements, newest
versions of drivers, and firmware documentation updates, as well as instant access to numerous other
product resources.
After signing up, you can quickly locate your products by selecting Business support and then Storage
under Product Category.
Other documentation
A complete library of related documentation is available on the following HP web site:
http://h18006.www1.hp.com/storage/saninfrastructure.html
Using IBM AIX Native MPIO with HP Enterprise Virtual Array storage systems
3
MPIO overview
Multi-Path IO is the storage multi-pathing solution part of the AIX base O,S starting with AIX 5.2 and
AIX 5.3. Storage-specific functionality can be added to the basic MPIO framework by providing
a vendor-specific path control module (PCM). The install package of the EVA MPIO solution
(devices.fcp.disk.HP.hsv.mpio.rte) provides among other management utilities, the AIX Object Database
Manager (ODM) device attributes required to define the EVA disk array devices as MPIO capable and to
instruct the MPIO driver to utilize the default PCM provided by IBM.
New features
This version provides support for:
• EVA XL AA (HSV200 HSV210)
• High Availability Cluster Multiprocessing (HACMP) when using enhanced concurrent volume
groups in the cluster
• ODM fileset 1.0.1.0
Supported hardware and software
Table 1 Supported hardware and software
Component
Hardware/Software
Operating system
IBM AIX 5.2 TL08 SP2 or later
IBM AIX 5.3 TL04 SP2
Native IBM host bus adapters
(HBAs)
FC5716
FC6228
FC6239
FC1957
FC1977
Storage system
EVA4000/6000/8000 running VCS 5.0 or
later
IMPORTANT:
IBM AIX 5.2 requires the following minimum fileset versions:
• devices.common.IBM.mpio.rte 5.2.0.87
• devices.fcp.disk.rte5.2.0.86
IBM AIX 5.3 requires the following minimum fileset versions:
• devices.common.IBM.mpio.rte 5.3.0.42
• devices.fcp.disk.rte 5.3.0.42
For information about supported coexisting storage systems, see the HP StorageWorks SAN design
reference guide on the following HP web site:http://h18002.www1.hp.com/products/storageworks/
san/documentation.html
4
Preparing for installation
To prepare your IBM AIX system for MPIO installation:
1.
2.
3.
4.
5.
6.
Set up the EVA disks and SAN configuration for multipathing. For details, see the HP
StorageWorks SAN design reference guide on the following HP web site:
http://h18002.www1.hp.com/products/storageworks/san/documentation.html
Ensure that the Vdisks are presented to the system with host type IBM AIX.
Ensure that all I/O paths to a set of LUNs are connected to the same type of HBA.
Verify that no AntemetA solution software is installed. Check for the Antemeta filesets below and
remove them before continuing with this installation:
• devices.fcp.hdi.pdisk.rte
• devices.fcp.hdi.hsv100.rte
• devices.fcp.hdi.hsv110.rte
• devices.fcp.hdi.hsv200.rte
• devices.fcp.hdi.hsv210.rte
Verify that your system has the required patches installed.
Download the devices.fcp.disk.HP.hsv.mpio.1.0.1.0.tar file from the following
HP web site:
http://h18006.www1.hp.com/products/sanworks/multipathoptions/index.html
Installing the ODM fileset
The ODM fileset installation routine verifies ODM definitions and checks fileset prerequisites. You can use
the System Management Interface Tool (SMIT) to install the update or you can install it manually.
Installing the ODM fileset manually
To install the ODM fileset manually, copy the .tar file into a separate dirctory and expand it to create a
TOC file, and then use the IBM AIX installp utility or SMIT to complete the installation.
The following example shows a manual installation:
#
#
#
#
mkdir /tmp/hsv
cp devices.fcp.disk.HP.hsv.mpio.1.0.1.0.tar /tmp/hsv
cd /tmp/hsv
tar xvf devices.fcp.disk.HP.hsv.mpio.1.0.1.0.tar
The fileset: devices.fcp.disk.HP.hsv.mpio.1.0.1.0.bff is extracted.
# inutoc $PWD
# installp –acd . –einstallp.log ALL
Using IBM AIX Native MPIO with HP Enterprise Virtual Array storage systems
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Recommendations
To ensure proper operation, HP recommends that you take the following action:
• Add a path to the HSV utilities in the /opt/hphsv/bin directory.
# PATH=$PATH:/opt/hphsv/bin
• Check the HBA error recovery policy (fc_err_recov) and make sure it is set to fast_fail.
# lsattr -El fscsi0
attach
switch
dyntrk
no
fc_err_recov delayed_fail
scsi_id
0x7b0500
sw_fc_class 3
How this adapter is CONNECTED
Dynamic Tracking of FC Devices
FC Fabric Event Error RECOVERY Policy
Adapter SCSI ID
FC Class for Fabric
False
True
True
False
True
# chdev -a fc_err_recov=fast_fail -l fscsi0
fscsi0 changed
# lsattr -El
attach
dyntrk
fc_err_recov
scsi_id
sw_fc_class
fscsi0
switch
no
fast_fail
0x7b0500
3
How this adapter is CONNECTED
Dynamic Tracking of FC Devices
FC Fabric Event Error RECOVERY Policy
Adapter SCSI ID
FC Class for Fabric
• Enter the following commands in the order shown to scan for new devices:
# cfgmgr
# lshsv
# lspath
6
False
True
True
False
True
Removing the ODM fileset
To remove the ODM fileset:
1. Remove HSV disk definitions using one of the following commands:
• Enter # rmhsv
• Enter # rmdev
• Enter # rmdev
instance and to
-d
–d –l hdiskn for each hdisk definition.
–dR –l fscsin to remove all hdisk devices from the Fibre Channel
remove the Fibre Channel driver.
IMPORTANT:
You must remove all HSV devices from the system in order to remove the ODM fileset
successfully.
2. Remove the ODM fileset using the IBM AIX installp utility:
# installp -u devices.fcp.disk.HP.hsv.mpio.rte
Using IBM AIX Native MPIO with HP Enterprise Virtual Array storage systems
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EVA disk attributes
IBM AIX native commands lists the default values for the EVA disk attributes in AIX. These values ensure
correct operation of your EVA storage system. Some attributes are allowed to be changed, including:
queue_depth, reserver_policy (no_reserve), and path priority.
IBM AIX native commands
This section describes the IBM AIX commands that you use to operate MPIO devices.
Table 2 IBM AIX native commands
Attribute
Default
value
PR_key_value N/A
Description
Notes
Sets the key value for persistent reservations
Persistent reservations are not
supported.
algorithm
fail_over
Sets the load balancing algorithm to
fail_over. All I/O uses a single path. The
remaining paths are in standby mode.
The value round_robin is not
supported.
hcheck_interval
60
Sets the path health feature to check each
device every 60 seconds. All devices are
checked, but not precisely at the same
time. hcheck_mode nonactive Specifies the
I/O paths monitored by the path health
checking feature:
• nonactive—Checks all I/O paths for
Failed status, and checks standby paths
for Used/Opened devices
• failed—Checks failed I/O paths
• enabled—Checks paths that are
enabled and opened
Paths that are not opened, are
not monitored.
queue_depth
8
Sets the queue depth
reserve_policy
Single
path
Sets the reserve policy to standard SCSI-2
reservations.
rw_timeout
60
Sets the read/write timeout to 60 seconds.
path
priority
1
Specifies the priority of each I/O path. A
priority of 1 specifies a primary path and
a priority 2 describes a secondary path.
This attribute determines which I/O path is
selected first and if a path fails which path
is selected next. Multiple paths can have
the same priority. If all paths have the same
priority, the path selection is based on when
each path was configured. This requires
the attribute algorithm to be fail_over.
Persistent reservations are not
supported.
Using this attribute static
LUN-based load balancing
can be implemented.
lspath
The command displays all devices on the MPIO paths and the state of each path. See the man page
for details
Syntax: lspath
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NOTE:
Changes in path availability are not reported immediately if the path is inactive. An attempted I/O
on the path updates its status.
chpath
The chpath command restores a repaired path to Enabled status. See the man page for details.
Syntax: chpath -l hdiskn -p parent_fscsi_driver [-w wwn,lunid] -s enable
HP AIX MPIO utilities
This section describes the utilities included in the ODM fileset.
lshba
The lshba utility displays information about the HBA, including the World Wide Name, HBA model,
firmware version, and slot.
Syntax: lshba
lshsv
The lshsv utility displays information about the EVA disks and I/O paths.
lshsv [-h] [-p] [-d|-e|-f|-m] [-l hdisk#]
-l hdisk#
List hdisk# only
-p
List path details
-d|-e|-f|-m
Status Disabled|Enabled|Failed|Missing
or
lshsv -s
-s
List array summary
When entered without optional parameters, the lshsv command displays a list of all EVA disks.
lshsv –h
The lshsv –h command displays a list of optional parameters.
lshsv [-h] [-p] [-d|-e|-f|-m] [-l hdisk#]
-l hdisk#
List hdisk# only
-p
List path details
-d|-e|-f|-m
Status Disabled|Enabled|Failed|Missing
or
lshsv -s
-s
List array summary
lshsv –p
The lshsv –p command displays a list of all I/O paths to the EVA disks.
lshsv –p –l hdiskn
The lshsv –p –l hdiskn command displays a list of all I/O paths to the specified disk. For example,
to see a list of the I/O paths connected to hdisk3, enter:
lshsv –p –l hdisk3
Using IBM AIX Native MPIO with HP Enterprise Virtual Array storage systems
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lshsv -s
lshsv –s lists a summary of all EVA disk arrays connected to the system.
hsvpaths
The hsvpaths command provides a summary of the HSV I/O paths.
Syntax: hsvpaths
rmhsv -d
The rmhsv -d command uncofigures and undefines (deletes) all EVA disk devices..
Syntax: rmhsv -d
Path health checking feature
The path health checking feature monitors the status of I/O paths. If an active path fails or is
disconnected, an attempted I/O causes an automatic failover to a standby path.
NOTE:
If a nonactive path fails, a link error is written to the errpt log.
When connectivity is restored to a failed path with health checking enabled, the path status changes
automatically from Failed to Enabled and the path becomes available.
NOTE:
Path checking does not monitor paths to devices that are not opened. As a result, if a non-opened device
is disconnected, it may be reported as Enabled.
Static LUN Based load balancing
Starting with MPIO 1.0.1.0, the path attribute "priority" has been introduced to specify a priority for
each path to specific LUN. MPIO will select failover or fail back, according to the settings of this path
attribute. A priority of 1 specifies a primary path and a value of 2 specifies a secondary path. Several
paths can have the same priority. If several paths do have the same priority, MPIO will select the path
which was configured first. If primary paths are available, MPIO will always utilize one of these paths
first. If no primary path is available, a secondary path will be used instead. Because the MPIO algorith
"fail_over" is being used, there is only one path active per LUN at a time. By defining a different primary
path for each LUN, a static LUN-based load balancing will be achieved distributing the I/O load of all
LUNs across the set of I/O paths. Combined with host based striping (partition-based striping of AIX) the
total I/O load is distributed evenly across all I/O paths and the load balancing becomes very effective. If
all paths have the priority 1, it indicates that no load balancing is being used.
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