Manual

Contents
1 Overview..................................................................................................6
Traditional library control path and drive connections without failover..............................................7
Basic path failover....................................................................................................................8
Basic data path port failover details.......................................................................................8
Basic control path failover details...........................................................................................9
Technology for basic control path failover.............................................................................11
Advanced path failover...........................................................................................................11
Driver operation during device open.....................................................................................12
Opening a connection to a library control path.....................................................................12
Driver operation during normal communications.....................................................................13
Path failure detection..........................................................................................................13
Path failure recovery...........................................................................................................13
Active and passive control path drives..................................................................................13
Library controller path failure recovery..................................................................................14
2 Enabling basic path failover......................................................................15
3 Installing advanced path failover................................................................16
Preparing the SAN.................................................................................................................16
Minimize host access..........................................................................................................16
Configure redundant connections.........................................................................................16
Review the SAN design guidelines.......................................................................................16
Preparing the library...............................................................................................................16
Preparing the host...................................................................................................................17
4 Preparing the switches and hosts for failover................................................18
Hardware-specific requirements for basic failover........................................................................18
Brocade switches...............................................................................................................18
Cisco switches...................................................................................................................19
Hardware-specific requirements for advanced path failover..........................................................19
B-Series switches................................................................................................................19
C-Series switches................................................................................................................19
H-Series switches................................................................................................................19
5 Configuring failover for the HP StoreEver ESL G3 Tape Libraries......................20
Configuring data path failover..................................................................................................20
Enabling data path failover.................................................................................................20
Verifying data path failover.................................................................................................21
Diagnosing basic data path failover.....................................................................................22
Disabling data path failover................................................................................................23
Configuring control path failover...............................................................................................23
Enabling control path failover..............................................................................................24
Configuration requirements after enabling control path failure..................................................25
Library configuration......................................................................................................25
SAN configuration........................................................................................................25
Verifying control path failover..............................................................................................26
Disabling control path failover.............................................................................................26
6 Configuring failover for HP StoreEver MSL6840 Tape Libraries.......................27
Configuring control path failover...............................................................................................27
Enabling control path failover..............................................................................................27
Configuration requirements after enabling basic control path failure.........................................28
Verifying control path failover..............................................................................................28
Configuring data path failover..................................................................................................29
Contents 3