T10000A and T10000B drives are exposed to an issue where VSM attached drives may see "SLS6788 - Invalid MIR" VTCS messages, causing the MVC to be marked as read only.

Asset ID:	1-73-1022274.1
Update Date:	2012-07-30
Keywords:

Solution Type FAB (standard) Sure

Solution 1022274.1 : T10000A and T10000B drives are exposed to an issue where VSM attached drives may see "SLS6788 - Invalid MIR" VTCS messages, causing the MVC to be marked as read only.

Impact

This issue can cause slightly slower performance during a search/position operation and causes the affected cartridge to be put into a read-only type status by VTCS (the tape will not be used to migrate any further VSM data).

Contributing Factors

This issue can occur on T10000A/B drives that are part of a Virtual Storage Manager (VSM) complex if RV.44.108/208 or 1.44.110/210 code version is installed in the drive.

Symptoms

The customer may start to see "SLS6788I" messages, and the Invalid MIR flag will be set for cartridges that are affected by this issue. This effectively puts the cartridge in a read-only status as the affected cartridge will not be selected for migration until the cartridge is drained.

Root Cause

RV.44.108/208 and 1.44.110/210 firmware versions added an additional check within the MIR. If these MIR validation tests fail, the drive will send back a tape alert for an Invalid MIR. It will also cause the MIR to only index blocks up to the point where the discrepancy occurs. This may cause high speed searches to take additional time, although the increase in time should not be significant.

Corrective Action

Workaround:

No workaround available – see Resolution section below.

Resolution:

The issue will be mitigated and then resolved in two steps;

1) Install special build microcode RE.44.110/210 code. This special build will remove the additional MIR check and remove the issue. This code is available through T3 Backline Support.

2) The change provided by the special code build will be embedded in GA released code which is targeted for the April 2010 time-frame in the 1.44.111/211 version.

Comments

If you suspect that your account is experiencing this issue, please contact Tape Technical Support for further instructions. A forced drive dump and the associated event-log files are required as part of the information necessary to identify whether your account is experiencing the identified issue.

To fix a tape in this condition you need to drain the affected cartridge and rewrite it on a drive running with RE.44.110/210 code or the GA 1.44.111/211 code due out in mid to late April 2010.

If customer is running well with the firmware that they currently have, do not install RV.44.x08 or 1.44.x10 code into any RTD at this time.

For information about FAB documents, its release processes, implementation strategies and billing information, go to the following URL:

http://tns.central/fab

For Sun Authorized Service Providers go to:

http://tns.central/SPE/fab/

In addition to the above you may email:

[email protected]

Internal Contributor/submitter
[email protected]

Internal Eng Responsible Engineer
[email protected] Responsible Manager: [email protected]

Internal Services Knowledge Engineer
[email protected]

Internal Eng Business Unit Group
NWS (Storage)

Internal Sun Alert & FAB Admin Info
23-Mar-2010: Completed draft and sent to Extended Review.
25-Mar-2010: No feedback from Ext Rvw - sending to Publish.

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