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Novell LINUX ENTERPRISE SERVER 11 - STORAGE ADMINISTRATION GUIDE 2-23-2010 Administration Manual Download Page 77

Managing Multipath I/O for Devices

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7.16  What’s Next

If you want to use software RAIDs, create and configure them before you create file systems on the 
devices. For information, see the following:

Š

Chapter 8, “Software RAID Configuration,” on page 79

Š

Chapter 10, “Managing Software RAIDs 6 and 10 with mdadm,” on page 89

Summary of Contents for LINUX ENTERPRISE SERVER 11 - STORAGE ADMINISTRATION GUIDE 2-23-2010

Page 1: ...Novell www novell com novdocx en 7 January 2010 AUTHORIZED DOCUMENTATION SLES 11 Storage Administration Guide SUSE Linux Enterprise Server 11 February 23 2010 Storage Administration Guide...

Page 2: ...or re export to entities on the current U S export exclusion lists or to any embargoed or terrorist countries as specified in the U S export laws You agree to not use deliverables for prohibited nucl...

Page 3: ...arks For Novell trademarks see the Novell Trademark and Service Mark list http www novell com company legal trademarks tmlist html Third Party Materials All third party trademarks and copyrights are t...

Page 4: ...4 SLES 11 Storage Administration Guide novdocx en 7 January 2010...

Page 5: ...dev disk by id Directory 22 2 7 Filters for Multipathed Devices 22 2 8 User Friendly Names for Multipathed Devices 23 2 9 Advanced I O Load Balancing Options for Multipath 23 2 10 Location Change for...

Page 6: ...evices 45 7 2 3 Using LVM2 on Multipath Devices 46 7 2 4 Using mdadm with Multipath Devices 46 7 2 5 Using noflush with Multipath Devices 46 7 2 6 Partitioning Multipath Devices 47 7 2 7 Supported Arc...

Page 7: ...naging Software RAIDs 6 and 10 with mdadm 89 10 1 Creating a RAID 6 89 10 1 1 Understanding RAID 6 89 10 1 2 Creating a RAID 6 90 10 2 Creating Nested RAID 10 Devices with mdadm 90 10 2 1 Understandin...

Page 8: ...ly 122 13 2 4 Configuring Online Targets with ietadm 123 13 3 Configuring iSCSI Initiator 124 13 3 1 Using YaST for the iSCSI Initiator Configuration 125 13 3 2 Setting Up the iSCSI Initiator Manually...

Page 9: ...5 1 Managing Multipath I O 138 A 6 June 22 2009 138 A 6 1 Managing Multipath I O 138 A 6 2 Managing Software RAIDs 6 and 10 with mdadm 139 A 6 3 Mass Storage over IP Networks iSCSI 139 A 7 May 21 200...

Page 10: ...10 SLES 11 Storage Administration Guide novdocx en 7 January 2010...

Page 11: ...enter your comments there Documentation Updates For the most recent version of the SUSE Linux Enterprise Server 11 Storage Administration Guide visit the Novell Documentation Web site for SUSE Linux...

Page 12: ...12 SLES 11 Storage Administration Guide novdocx en 7 January 2010...

Page 13: ...he file systems show different performance characteristics It is extremely important to maintain metadata intact because otherwise all data on the file system could become inaccessible inode A data st...

Page 14: ...strengths might help understand why it was and in some areas still is the favorite Linux file system of many Linux users Solidity and Speed on page 14 Easy Upgradability on page 14 Solidity and Speed...

Page 15: ...ling file systems follow the metadata only journaling approach This means your metadata is always kept in a consistent state but this cannot be automatically guaranteed for the file system data itself...

Page 16: ...ty of the nodes in a cluster OCFS2 includes a simple heartbeat implementation To avoid problems arising from various nodes directly accessing the file system OCFS2 also contains a distributed lock man...

Page 17: ...es both data and metadata integrity but uses journaling only for metadata 1 2 5 XFS Originally intended as the file system for their IRIX OS SGI started XFS development in the early 1990s The idea beh...

Page 18: ...he contents of a file are not distributed all over the file system 1 3 Other Supported File Systems Table 1 1 summarizes some other file systems supported by Linux They are supported mainly to ensure...

Page 19: ...These are as follows File Size On 32 bit systems files cannot exceed 2 TB 241 bytes File System Size File systems can be up to 273 bytes in size However this limit is still out of reach for the curre...

Page 20: ...erFSprogs http chichkin_i zelnet ru namesys XFS A High Performance Journaling Filesytem http oss sgi com projects xfs OCFS2 Project http oss oracle com projects ocfs2 A comprehensive multipart tutoria...

Page 21: ...nagement solution is deprecated All EVMS management modules have been removed from the SUSE Linux Enterprise Server 11 packages Your EVMS managed devices should be automatically recognized and managed...

Page 22: ...ecause they automatically point to the correct device See the following sections for more information about how this behavior change affects other features Section 2 7 Filters for Multipathed Devices...

Page 23: ...lowing advanced I O load balancing options are available in additon to round robin for Device Mapper Multipath Least pending Length load balancing Service time For information see path_selector in Und...

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Page 25: ...3 2 Multipath Support Linux supports using multiple I O paths for fault tolerant connections between the server and its storage devices Linux multipath support is disabled by default If you use a mult...

Page 26: ...www amanda org http www amanda org 3 5 2 Commercial Backup and Antivirus Support Novell Open Enterprise Server OES 2 Support Pack 1 for Linux is a product that includes SUSE Linux Enterprise Server SL...

Page 27: ...es on page 29 Section 4 5 Configuring Logical Volumes on page 30 Section 4 6 Direct LVM Management on page 32 Section 4 7 Resizing an LVM Partition on page 32 4 1 Understanding the Logical Volume Mana...

Page 28: ...servers in the running system With these features using LVM already makes sense for heavily used home PCs or small servers If you have a growing data stock as in the case of databases music archives...

Page 29: ...l partitions with either the Linux LVM or Linux native type No swap or DOS partitions are shown If a partition is already assigned to a volume group the name of the volume group is shown in the list U...

Page 30: ...ed to the configuration of logical volumes 4 5 Configuring Logical Volumes After the volume group has been filled with physical volumes use the next dialog see Figure 4 4 to define the logical volumes...

Page 31: ...e to distribute the data stream in the logical volume among several physical volumes striping If these physical volumes reside on different hard disks this generally results in a better reading and wr...

Page 32: ...Resizing an LVM Partition You can increase the size of a logical volume by using the YaST partitioner or by using the lvextend command YaST uses parted 8 to grow the partition To extend an LV there mu...

Page 33: ...olume lvextend L size dev vgname lvname For size specify the amount of space you want to add to the logical volume such as 10GB Replace dev vgname lvname with the Linux path to the logical volume such...

Page 34: ...34 SLES 11 Storage Administration Guide novdocx en 7 January 2010...

Page 35: ...that Support Resizing on page 35 Section 5 1 2 Increasing the Size of a File System on page 35 Section 5 1 3 Decreasing the Size of a File System on page 36 5 1 1 File Systems that Support Resizing Th...

Page 36: ...h the resize2fs command 1 Open a terminal console then log in as the root user or equivalent 2 Increase the size of the file system using one of the following methods To extend the file system size to...

Page 37: ...il the resizing is completed before continuing 3 If the file system is not mounted mount it now For example to mount an ReiserFS file system for device dev sda2 at mount point home enter mount t reise...

Page 38: ...py 3 Decrease the size of the file system on a device called dev sda1 by entering resize_reiserfs s size dev sda2 Replace size with the desired size in bytes You can also specify units on the value su...

Page 39: ...s regardless of their order of recognition or the connection used for the device The udev tools examine every appropriate block device that the kernel creates to apply naming rules based on certain bu...

Page 40: ...e label name when the partition is mounted You can use the UUID as criterion for assembling and activating software RAID devices When a RAID is created the md driver generates a UUID for the device an...

Page 41: ...ollowing to place the UUID in the etc fstab file Open YaST to System Partitioner select the device of interest then modify Fstab Options Edit the etc fstab file to modify the system device from the lo...

Page 42: ...3aefde77a 6 Edit the boot efi SuSE elilo conf file to modify the system device from the location to the UUID For example change dev sda1 reiserfs acl user_xattr 1 1 to UUID e014e482 1c2d 4d09 84ec 61b...

Page 43: ...Devices without Rebooting on page 73 Section 7 12 Viewing Multipath I O Status on page 74 Section 7 13 Managing I O in Error Situations on page 75 Section 7 14 Resolving Stalled I O on page 76 Section...

Page 44: ...Storage Arrays for Multipathing on page 47 7 2 1 Guidelines for Multipathing Use the guidelines in this section when planning your multipath I O solution Prerequisites on page 44 Vendor Provided Mult...

Page 45: ...ultipathing management running underneath High Availability Solutions High availability solutions for clustering typically run on top of the multipathing server For example the Distributed Replicated...

Page 46: ...ultipathing is configured filter a dev disk by id dm uuid mpath r 3 If you are also using LVM2 on non multipathed devices make the necessary adjustments to suit your setup filter a dev disk by id r 4...

Page 47: ...eboot This triggers udevd to fill in the dev disk by symlinks The main benefit is that you can call kpartx with the new parameters without rebooting the server SUSE Linux Enterprise Server 9 In SUSE L...

Page 48: ...cted the default settings for multipathing apply If you want non default settings you must manually create and configure the etc multipath conf file For information see Section 7 4 5 Creating and Conf...

Page 49: ...hat Are Automatically Detected for Multipathing on page 48 Storage Arrays that Require Specific Hardware Handlers Storage arrays that require special commands on failover from one path to the other or...

Page 50: ...d balancing algorithms than round robin The user space component of DM MP takes care of automatic path discovery and grouping as well as automated path retesting so that a previously failed path is au...

Page 51: ...also presents the LUNs to the multipath component so that the operating system knows about redundant paths If the primary controller fails the second controller takes over and it serves all LUNs In so...

Page 52: ...athed devices Just as for LVM2 mdadm requires that the devices be accessed by the ID rather than by the device node path Therefore the DEVICE entry in etc mdadm conf should be set as follows DEVICE de...

Page 53: ...device node name such as dev sdb as shown by udev in the DEVNAME variable or in the major minor format Selectively suppress a multipath map and its device mapped partitions multipath f Display potenti...

Page 54: ...s tools Install the Linux HBA driver module Upon module installation the driver automatically scans the HBA to discover any SAN devices that have permissions for the host It presents them to the host...

Page 55: ...Linux Enterprise Server 9 In SUSE Linux Enterprise Server 9 if you want to partition the device you should configure its partitions before you attempt to configure multipathing by using the Partition...

Page 56: ...minal console then log in as the root user or equivalent 2 At the terminal console prompt enter insserv multipathd 7 4 5 Creating and Configuring the etc multipath conf File The etc multipath conf fil...

Page 57: ...n be used no further configuration of the etc multipath conf file is required 5 Save the file Verifying the Setup in the etc multipath conf File After setting up the configuration you can perform a dr...

Page 58: ...ommend that you do not use aliases for the root device because the ability to seamlessly switch off multipathing via the kernel command line is lost because the device name differs For an example of m...

Page 59: ...conf The etc multipath conf file should contain a defaults section where you can specify default behaviors If the field is not otherwise specified in a device section the default setting is applied fo...

Page 60: ...path conf File Changes to the etc multipath conf file cannot take effect when multipathd is running After you make changes save and close the file then do the following to apply the changes 1 Stop the...

Page 61: ...Configuring ALUA on page 67 Section 7 6 5 Reporting Target Path Groups on page 69 7 6 1 Configuring the Path Failover Policies Use the multipath command with the p option to set the path failover pol...

Page 62: ...For a given device the paths with the same priorities belong to the same priority group Table 7 5 Multipath Attributes Multipath Attribute Description Values user_friendly_names Specifies whether to u...

Page 63: ...fetched in sys class fc_transport target node_name path_checker Determines the state of the path directio Default in multipath tools version 0 4 8 and later Reads the first sector that has direct I O...

Page 64: ...cy considers the number of unserviced requests pending on a path and selects the path with least count of pending service requests This policy is especially useful when the SAN environment has heterog...

Page 65: ...s is the default bin true Use this value when the group_by_priority is not being used The prioritizer programs generate path priorities when queried by the multipath command The program names must beg...

Page 66: ...method to use for paths uniform Default All paths have the same round robin weightings priorities Each path s weighting is determined by the path s priority times the rr_min_io setting no_path_retry...

Page 67: ...00000045317563 2 0x10000000c95ebeb4 0x200200a0b8122c6e 2 0 0 2 sdd 3600a0b8000122c6d0000000345317524 50 0x10000000c95ebeb4 0x200200a0b8122c6e 2 0 0 3 sde 3600a0b80000fd6320000000245317593 2 0x10000000...

Page 68: ...SI device you want to manage The device must be a SCSI device that supports the Report Target Port Groups sg_rtpg 8 command Use one of the following formats for the device node name The full Linux dir...

Page 69: ...out settings for your HBA to disable failover at the HBA level to allow the failure to propagate up to the multipath I O layer as fast as possible where the I O can be redirected to another healthy p...

Page 70: ...ing software RAID For example you might need to configure multipathing for devices in a software RAID under the following circumstances If you create a new software RAID as part of the Partitioning se...

Page 71: ...D s component devices should match their Device Mapper Multipath device names that are listed as the symbolic links of devices in the dev disk by id directory 8 Make a new initrd to ensure that the De...

Page 72: ...ault 0 L NUM Activates scanning for LUNs 0 to NUM Default 0 w Scans for target device IDs 0 to 15 Default 0 to 7 c Enables scanning of channels 0 or 1 Default 0 r remove Enables removing of devices De...

Page 73: ...rompt enter multipath You can now configure the new device for multipathing 7 11 Scanning for New Partitioned Devices without Rebooting Use the example in this section to detect a newly added multipat...

Page 74: ...ultipath ll option runs the path checker updates the path information then displays the current status information This option always the displays the latest information about the path status 1 At a t...

Page 75: ...e_if_no_path leads to I O being queued indefinitely unless a path is reinstated make sure that multipathd is running and works for your scenario Otherwise I O might be stalled indefinitely on the affe...

Page 76: ...tipath I O on SUSE Linux Enterprise Server see the following additional resources in the Novell Support Knowledgebase How to Setup Use Multipathing on SLES http support novell com techcenter sdb en 20...

Page 77: ...What s Next If you want to use software RAIDs create and configure them before you create file systems on the devices For information see the following Chapter 8 Software RAID Configuration on page 7...

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Page 79: ...e offers the option of combining several hard disks into one soft RAID system RAID implies several strategies for combining several hard disks in a RAID system each with different goals advantages and...

Page 80: ...sk might create a bottleneck for write access Nevertheless Level 4 is sometimes used 8 1 5 RAID 5 RAID 5 is an optimized compromise between Level 0 and Level 1 in terms of performance and redundancy T...

Page 81: ...l partitions with either the Linux RAID or Linux native type No swap or DOS partitions are shown If a partition is already assigned to a RAID volume the name of the RAID device for example dev md0 is...

Page 82: ...w one partitioned the same way Then restart your system and enter the command mdadm dev mdX add dev sdX Replace X with your particular device identifiers This integrates the hard disk automatically in...

Page 83: ...ant Striping RAID 5 requires three or more devices The hard drives should be similarly sized The RAID assumes the size of the smallest drive The block storage devices can be any combination of local i...

Page 84: ...sted only once in the list of hard disks 9 4 Creating a Software RAID Device for the Root Partition 1 Proceed with the YaST install of SUSE Linux Enterprise 11 until you reach the Installation Setting...

Page 85: ...AID 6 Create the RAID device 6a In the System View panel select RAID then click Add RAID on the RAID page The devices that you prepared in Step 5 are listed in Available Devices 6b Under RAID Type sel...

Page 86: ...KB The default chunk size for a RAID 0 Striping is 32 KB Available chunk sizes are 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB or 4 MB 6f Under Formatting Options select Format partiti...

Page 87: ...ath 7 On the Expert Partitioner page click Accept The new proposal appears under Partitioning on the Installation Settings page For example the setup for the 8 Continue with the install Whenever you r...

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Page 89: ...hat allows for additional fault tolerance by using a second independent distributed parity scheme dual parity Even if two of the hard disk drives fail during the data recovery process the system conti...

Page 90: ...the RAID 6 device dev md0 6 Reboot the server The RAID 6 device is mounted to local 7 Optional Add a hot spare to service the RAID array For example at the command prompt enter mdadm dev md0 a dev sde...

Page 91: ...r device in the RAID 0 is mirrored individually multiple disk failures can be tolerated and data remains available as long as the disks that fail are in different mirrors You can optionally configure...

Page 92: ...the etc mdadm conf file to add entries for the component devices and the RAID device dev md2 6 Edit the etc fstab file to add an entry for the RAID 1 0 device dev md2 7 Reboot the server The RAID 1 0...

Page 93: ...fs reiserfs dev md2 Modify the command if you want to use a different file system 5 Edit the etc mdadm conf file to add entries for the component devices and the RAID device dev md2 6 Edit the etc fst...

Page 94: ...ded by the number of replicas For example if you specify 2 replicas for an array created with 5 component devices a copy of each block is stored on two different devices The effective storage size for...

Page 95: ...r Layout The far layout stripes data over the early part of all drives then stripes a second copy of the data over the later part of all drives making sure that all copies of a block are on different...

Page 96: ...mmand At the command prompt enter all on the same line mdadm create dev md3 run level 10 chunk 4 raid devices 4 dev sdf1 dev sdg1 dev sdh1 dev sdi1 4 Create a Reiser file system on the RAID 10 device...

Page 97: ...e data is now across all devices An example of this process is given in the following procedure 1 Create a degraded RAID 1 device dev md0 using one single drive dev sd1 enter the following at the comm...

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Page 99: ...g a Software RAID The mdadm 8 tool supports resizing only for software RAID levels 1 4 5 and 6 These RAID levels provide disk fault tolerance so that one component partition can be removed at a time f...

Page 100: ...s no or reduced disk fault tolerance Even for RAIDs that can tolerate multiple concurrent disk failures do not remove more than one component partition at a time WARNING If a RAID does not have disk f...

Page 101: ...ccessed by the system When the replacement device is added back into the RAID it takes much longer to synchronize the data because all of the data that was on the original device must be rebuilt 5 Re...

Page 102: ...resized as you expected you must reboot then try this procedure again 11 2 3 Increasing the Size of the File System After you increase the size of the array see Section 11 2 2 Increasing the Size of t...

Page 103: ...erminal console then log in as the root user or equivalent 2 Increase the size of the file system on the software RAID device called dev md0 using one of the following methods To extend the file syste...

Page 104: ...your file system The procedures in this section use the device name dev md0 for the RAID device Make sure to modify commands to use the name of your own device Ext2 or Ext3 The Ext2 and Ext3 file syst...

Page 105: ...The h option print sizes in human readable format such as 1K 234M or 2G 11 3 2 Decreasing the Size of Component Partitions Resize the RAID s component partitions one at a time For each component part...

Page 106: ...r the correct component partition 7 If you get a message that tells you that the kernel could not re read the partition table for the RAID you must reboot the computer after resizing all of its compon...

Page 107: ...novdocx en 7 January 2010 mdadm D dev md0 grep e Array Size e Device Size 5 Do one of the following If your array was successfully resized you are done If your array was not resized as you expected y...

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Page 109: ...iSNS Discovery Domains on page 112 Section 12 4 Starting iSNS on page 116 Section 12 5 Stopping iSNS on page 116 Section 12 6 For More Information on page 116 12 1 How iSNS Works For an iSCSI initiat...

Page 110: ...management implementations Improves scalability compared to other discovery methods An example of the benefits iSNS provides can be better understood through the following scenario Suppose you have a...

Page 111: ...atically on server startup Manually Default The iSNS service must be started manually by entering rcisns start or etc init d isns start at the server console of the server where you install it 6 Speci...

Page 112: ...d to the default discovery domain To create a new discovery domain 1 Start YaST and under Network Services select iSNS Server 2 Click the Discovery Domains tab The Discovery Domains area lists all dis...

Page 113: ...discovery domain but it is not active and the iSNS service does not function unless you add the discovery domain to a discovery domain set A default discovery domain set named default DDS is automatic...

Page 114: ...does not delete the discovery domain Adding an discovery domain to a set allows a not yet registered iSNS discovery domain to be added as a member of the discovery domain set 3 Click the Create Discov...

Page 115: ...ode is automatically added to the list iSNS database again when you restart the iSCSI service or reboot the server unless you remove or comment out the iSNS portion of the iSCSI configuration file 4 C...

Page 116: ...also be configured to start automatically each time the server is rebooted 1 Start YaST and under Network Services select iSNS Server 2 With the Service tab selected specify the IP address of your iSN...

Page 117: ...evices and servers iSCSI target software runs on the target server and defines the logical units as iSCSI target devices iSCSI initiator software runs on different servers and connects to the target d...

Page 118: ...ection 13 1 2 Installing the iSCSI Initiator Software on page 118 13 1 1 Installing iSCSI Target Software Install the iSCSI target software on the server where you want to create iSCSI target devices...

Page 119: ...Devices on page 119 Partitioning Devices in a Virtual Environment on page 119 Partitioning Devices 1 Log in as the root user then open YaST 2 Select System Partitioner 3 Click Yes to continue through...

Page 120: ...ect Network Services iSCSI Target YaST opens to the iSCSI Target Overview page with the Service tab selected 3 In the Service Start area select one of the following When booting Automatically start th...

Page 121: ...he authentication set here is used for the discovery of services not for accessing the targets If you do not want to restrict the access to the discovery use No Authentication If authentication is nee...

Page 122: ...ported Just keep iSNSAccessControl no All direct iSCSI authentication can be done in two directions The iSCSI target can require the iSCSI initiator to authenticate with the IncomingUser which can be...

Page 123: ...hanges should be done in the main configuration file etc ietd conf but also made manually to the current configuration with the administration utility ietadm To create a new iSCSI target with a LUN fi...

Page 124: ...utility are not permanent for the system These changes are lost at the next reboot if they are not added to the etc ietd conf configuration file Depending on the usage of iSCSI in your network this mi...

Page 125: ...rd on server boots Discovered Targets Discovered Targets provides the possibility of manually discovering iSCSI targets in the network Configuring the iSCSI Initiator on page 125 Discovering iSCSI Tar...

Page 126: ...IP address of the iSNS server and port The default port is 3205 3 On the iSCSI Initiator Overview page click Finish to save and apply your changes Discovering iSCSI Targets Manually Repeat the follow...

Page 127: ...stead the configuration file etc iscsid conf must be edited to provide the information To add your password information for the discovery add the following lines to the end of etc iscsid conf discover...

Page 128: ...P node session auth username joe node session auth password node session auth username_in empty node session auth password_in empty node session timeo replacement_timeout 0 node session err_timeo abor...

Page 129: ...performance benchmarks or just describing hardware solutions Important pages for more information about open iscsi are Open iSCSI Project http www open iscsi org AppNote iFolder on Open Enterprise Se...

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Page 131: ...nal volume Snapshot uses copy on write technology to detect when data changes in an original data block It copies the value it held when the snapshot was taken to a block in the snapshot volume then a...

Page 132: ...le log in as the root user then enter lvdisplay snap_volume For example lvdisplay dev vg01 linux01 snap Logical volume LV Name dev lvm linux01 VG Name vg01 LV UUID QHVJYh PR3s A4SG s4Aa MyWN Ra7a HL47...

Page 133: ...cribes how to work around known issues for devices software RAIDs multipath I O and volumes Section 15 1 Is DM MPIO Available for the Boot Partition on page 133 15 1 Is DM MPIO Available for the Boot...

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Page 135: ...on A 5 August 3 2009 on page 138 Section A 6 June 22 2009 on page 138 Section A 7 May 21 2009 on page 139 A 1 February 23 2010 Updates were made to the following sections The changes are explained bel...

Page 136: ...id as shown in the above example instead of the sample path of lib udev scsi_id that is found in the sample file usr share doc packages multipath tools multipath conf synthetic file and in the default...

Page 137: ...ipath I O for Devices The following changes were made to this section Location Change Section 5 1 1 File Systems that Support Resizing on page 35 The resize2fs utility supports online or offline resiz...

Page 138: ...Software RAIDs 6 and 10 with mdadm on page 139 Section A 6 3 Mass Storage over IP Networks iSCSI on page 139 A 6 1 Managing Multipath I O The following changes were made to this section Configuring D...

Page 139: ...ction 7 11 Scanning for New Partitioned Devices without Rebooting on page 73 Step 7 on page 73 replaces old Step 7 and Step 8 Location Change Section 10 4 Creating a Degraded RAID Array on page 96 To...

Page 140: ...s If you are using zSeries devices you must manually create and configure the etc multipath conf file to specify the values For information see Configuring Default Settings for zSeries in etc multipat...

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