Linux Device Addressing, Everything is a file | IBM AIX-AK FZK 2005

IBM Systems Group

Linux Device Addressing

Everything is a file!

brw-rw----	1	root	disk	8,	0 2003-03-14	14:07 /dev/sda
brw-rw----	1	root	disk	8,	1 2003-03-14	14:07 /dev/sda1
brw-rw----	1	root	disk	3,	0 2003-03-14	14:07 /dev/hda
crw-rw----	1	root	disk	9,	0 2003-03-14	14:07 /dev/st0
crw-rw----	1	root	disk	9,	96 2003-03-14	14:07 /dev/st0a
crw-rw----	1	root	disk	9,	32 2003-03-14	14:07 /dev/st0l
crw-rw----	1	root	disk	9,	64 2003-03-14	14:07 /dev/st0m
	AIX-AK FZK 2005					© 2005 IBM Corporation

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IBM AIX-AK FZK 2005 manual Linux Device Addressing, Everything is a file

Contents

AIX AK April 2005 Forschungszentrum Karlsruhe IBM Storage with Linux Topics  What is supported What Is Supported IBM Storage Support for Linux PLinux Support Disk  DS6000, DS8000 SLES8, SLES9, RH-EL DS4000 SLES8, SLES9, RH-EL  LTO Sles 8, Sles 9, RH-EL PLinux Support Tape 359x Sles 8, Sles 9, RH-EL  Parallel Scsi attachment also supported  Advanced Linux Scsi Subsystem Everything is a file Linux Device Addressing Upper level Design Linux Kernel Version Storage Changes in Linux Kernel Still there Wellknown Linux Scsi Limitations Other Problems and Pitfalls  Multiple LUN support of RH-EL  DS4000 Specific ESS, DS6000, DS8000 Specific  Linux Kernel Limits Large filesystems support Multipathing Scenarios Multipathing Concepts  Two multipathing solutions available LUN Transfer to Alternate Controller DS4000 transfers LUNs to alternate controller LUN Thrashing Scenario LUN Thrashing Scenario LUN Thrashing Scenario Multipathing with Rdac  Must run mppUpdate after each configuration change Rdac Shared Data Scenario Rdac Shared Data Scenario Rdac Shared Data Scenario Preferred Path  DS6000 uses concept of preferred path SDD knows preferred path automatically Preferred Path Shared Data Scenario Preferred Path Shared Data Scenario Preferred Path Shared Data Scenario Preferred Path Shared Data Scenario  ESS and DS8000 have independent host ports Host Ports Independent of Controller Independent Host Port Shared Data Scenario Independent Host Port Shared Data Scenario Independent Host Port Shared Data Scenario Tape Specifics  Daemon IBMtaped IBMtape driver  Build and install using make  Provides IBMtapeUtil For download as source code Use LTO Devices  Native 3rd party applications Native Library Management Medium Changer Failover One driver for all HBAs Tape and Disk Connected to the Same HBA Questions & Discussion ESS / DS6000 / DS8000 Resources DS4000 Resources LTO Resources Redbooks White Papers Legal Notices