AIX Does Not Detect the VTL / Library after Installing Drivers

Overview

This topic describes the steps needed to reconfigure the FC adapter on a DXi system to solve a problem in which the OS does not detect the robot/VTL, even after all drivers have been installed and configured.

This article has the following sections:

Symptom
DXi Configuration Information
Overall System Configuration
Attempts to Detect Devices After Applying All ATAPE Drivers and Current HBA Drivers
Cause
Solution

Symptom

The customer was trying to get the VTL medium changer to show up in AIX 6.1 TL 7 but was unable to do so.

DXi Configuration Information

The customer had three DXi systems, each with the following installation/configuration:

Dxi Platform:	Drambuie - DXi8500
DXi Version:	2.2.1.3
DXi Build Number:	51139
Client OS:	AIX
Client App:	Tivoli Storage Manager
Client App Ver:	5.5

Overall System Configuration

Host Hardware / Software

IBM 9117- MMB
System Firmware:	AM720_090
LPAR AIX:	6.1.7.15
OS:	AIX 6.1 (TL 7)
ISV
TSM Server:	Version 5, Release 5, Level 0.0 ATAPE 12.1.5.0

Each system has a Quantum i6k (SN 263104491 - 33x HP LTO5 FC drives)

Quantum Hardware / Software

System:	DXi8500
Software Version:	2.2.1.3
TSM:	Server Version 5, Release 5, Level 6.100
IBM ATAPE Driver:	12.1.5.0

8Gb PCI Express Dual Port FC Adapter / Host Bus Adapters, Model: 10N9824 – for information, see http://pic.dhe.ibm.com/infocenter/powersys/v3r1m5/index.jsp?topic=%2Fiphcd%2Ffc5735.htm

Notes:

Drives + medium changer appear OK (have been running > 7 years).
Each system has an EMC (860) VTL partition assigned: IBM Ultrium-TD1 drives + medium changer (STK L180).
All libraries appear to be OK (have been running > 1 year).
After installing the DXi8500s and trying to allocate the resources to the TSM Servers, the drives showed up, but the OS was unable to discover a medium changer from the DXi8500s.
Customer had most recently applied the latest ATAPE to AIX, but it still did not define the Quantum changer. The latest ATAPE 12.6.5.0 drivers (dated Aug 2013) were applied on the system, but it still could not create the medium changer for the DXi systems.

Attempts to Detect Devices After Applying All ATAPE Drivers and Current HBA Drivers

Command Given:

b003227[AIX_Host]-/home/AIX_Host> lslpp -l | grep -i ATAPE

Output:

Atape.driver 12.6.5.0 COMMITTED IBM AIX Enhanced Tape and
FYI.

When listing the current configured libraries on this system, we got the following:

TSM Device Name   Vendor      Product ID     Firmware      World Wide Name           Serial Number
--------------- -------- ---------------- -------- ----------------------- ----------------------
/dev/lb0         ADIC      Scalar i2000        650Q              N/A            ADIC263104491_LL0
/dev/lb1         ADIC      Scalar i2000        650Q              N/A            ADIC263104491_LL2
/dev/lb2         STK       L180                0306              N/A            711170001F
/dev/lb3         STK       L180                0306              N/A            7111700000

The first two (2) devices are two Quantum i2k partitions, emulating a Scalar i2000 Library. The last two (2) devices are DataDomain VTL libraries, emulating an STK L180. But nothing is being created for the DXi!

Command Given:

b003227[AIX_Host]-/home/AIX_Host> lslpp -l | grep -i atape

Output:

Atape.driver 12.6.5.0 COMMITTED IBM AIX Enhanced Tape and re-ran the *cfmgr*:

cfgmgr: 0514-621 WARNING: The following device packages are required for
device support but are not currently installed.
devices.fcp.changer

We re-ran the *mkdev* through smitty ..

Output:

discover_fc_devices:can not open /dev/fscsi3
TSM Define Methods didnt/couldnt define any devices !!!!

NOTE: We also tried the Use CCL checkbox under host access. This had no impact.

The SR was then escalated -- all drivers were confirmed to be the latest.

Cause

Device discovery was detecting the DXi8500, but the discovery was immediately dropped, and the DXi8500 was not shown to the OS. After investigating, we noted that in this particular host/customer site, the majority of the time, the FC devices were multipath-aware (SAN disk LUNs).

By default, the customer had enabled dynamic tracking and fast failover on their FC adapters. However, these settings are NOT supported for multipath-aware devices (such as tape devices, and some VTL devices – and now, specifically for Quantum equipment). These HBA parameters needed to be reconfigured to get the VLT/Library to be seen correctly.

Solution

Note: This solution works for either a physical HBA assigned to the LPAR, or a NPIV HBA assigned from a VIOS.

To get the library/VTGL to be seen by the OS, we reconfigured the dynamic tracking and FC error recovery settings as follows:

$ chdev -l fscsi# -a dyntrk=no -P
$ chdev -l fscsi# -a fc_err_recov=delayed_fail -P

Discovery of the VTL now succeeded. The medium changer now showed up, in this particular case, as /dev/lb4:

NOTE: These two parameters may not exist on all HBAs, but there may be a parameter that may be equivalent. In this particular case, the HBA was an 8Gb PCI Express Dual Port FC Adapter / Host Bus Adapters, Model 10N9824.