Introduction - Red Hat ENTERPRISE LINUX 5.5 - ONLINE STORAGE GUIDE Manual

Online Storage Guide
6. Removing a Path to a Storage Device ................................................................................... 12
7. Adding a Storage Device or Path ........................................................................................... 12
8. Configuring a Fibre-Channel Over Ethernet Interface ............................................................. 14
9. Scanning Storage Interconnects ............................................................................................. 14
10. iSCSI Discovery Configuration ............................................................................................. 15
11. Configuring iSCSI Offload and Interface Binding ................................................................... 16
11.1. Viewing Available iface Configurations ....................................................................... 17
11.2. Configuring an iface for Software iSCSI ..................................................................... 18
11.3. Configuring an iface for iSCSI Offload ....................................................................... 18
11.4. Binding/Unbinding an iface to a Portal ....................................................................... 19
12. Scanning iSCSI Interconnects .............................................................................................. 20
13. Logging In to an iSCSI Target ............................................................................................. 22
14. Resizing an Online Logical Unit ........................................................................................... 23
14.1. Resizing Fibre Channel Logical Units ........................................................................ 23
14.2. Resizing an iSCSI Logical Unit .................................................................................. 23
14.3. Updating the Size of Your Multipath Device ............................................................... 24
15. Adding/Removing a Logical Unit Through rescan-scsi-bus.sh ................................................. 25
16. Modifying Link Loss Behavior .............................................................................................. 25
16.1. Fibre Channel .......................................................................................................... 26
16.2. iSCSI Settings With dm-multipath ......................................................................... 27
16.3. iSCSI Root ............................................................................................................... 28
17. Controlling the SCSI Command Timer and Device Status ...................................................... 29
18. Troubleshooting ................................................................................................................... 30
A. Revision History
Index

1. Introduction

It is often desirable to add, remove or re-size storage devices while the operating system is running,
and without rebooting. This manual outlines the procedures that may be used to reconfigure storage
devices on Red Hat Enterprise Linux 5 host systems while the system is running. It covers iSCSI and
Fibre Channel storage interconnects; other interconnect types may be added it the future.
The Online Storage Reconfiguration guide focuses on adding, removing, modifying, and monitoring
storage devices. It does not discuss the Fibre Channel or iSCSI protocols in detail. For more
information about these protocols, refer to other documentation.
This manual assumes that you have advanced working knowledge of Red Hat Enterprise Linux
5, along with first-hand experience in managing storage devices in Linux. Before consulting this
book, verify if your host bus adapter vendor or hardware vendor have their own documentation. It is
recommended that you consult such documents in conjunction with this manual.
Note
This manual makes reference to various sysfs objects. Red Hat advises that the sysfs
object names and directory structure are subject to change in major Red Hat Enterprise
Linux 5 releases. This is because the upstream Linux kernel does not provide a stable
internal API. For guidelines on how to reference sysfs objects in a transportable way,
refer to the document Documentation/sysfs-rules.txt in the kernel source tree for
guidelines.
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