OpenVMS__STORAGE ALPSHAD12_061 Alpha V6.1 Shadowing ECO Summary
NOTE: An OpenVMS saveset or PCSI installation file is stored
on the Internet in a self-expanding compressed file.
The name of the compressed file will be kit_name-dcx_vaxexe
for OpenVMS VAX or kit_name-dcx_axpexe for OpenVMS Alpha.
Once the file is copied to your system, it can be expanded
by typing RUN compressed_file. The resultant file will
be the OpenVMS saveset or PCSI installation file which
can be used to install the ECO.
Copyright (c) Digital Equipment Corporation 1996. All rights reserved.
PRODUCT: Volume Shadowing for OpenVMS Alpha
OP/SYS: OpenVMS Alpha
COMPONENT: Shadow Driver
SOURCE: Digital Equipment Corporation
ECO INFORMATION:
ECO Kit Name: ALPSHAD12_061
ECO Kits Superseded by This ECO Kit: ALPSHAD11_061
ALPSHAD10_061
ECO Kit Approximate Size: 1062 Blocks
Kit Applies To: OpenVMS Alpha V6.1, V6.1-1H1, V6.1-1H2
System/Cluster Reboot Necessary: Yes
Installation Rating: 2 - To be installed on all systems running
the listed version of OpenVMS and
using the following feature:
Volume Shadowing.
NOTE: In order to receive the full fixes listed in this kit,
the following remedial kits also need to be installed:
ALPSHAD09_061
ECO KIT SUMMARY:
An ECO kit exists for Volume Shadowing on Alpha V6.1 through
V6.1-1H2. This kit addresses the following problems:
Problems Addressed in ALPSHAD12_061:
o During a Bad Block Recovery operation, if the source member of
the shadow set cannot be found by the SHDRIVER, a SHADDETINCON
system crash will occur.
Problems Addressed in ALPSHAD11_061:
o An application I/O doing either a read or a write may fail.
This can occur even though only one member of a multiple
member shadow set is unable to complete the requested I/O.
This results in the shadow set members being removed from the
set. The I/O will be returned to the application with the
appropriate read or write error.
o Due to an incorrect recorded MSCP flag field, segmented I/Os
fail with invalid MSCP modifiers errors.
o Due to various code problems ,queue corruption, IRPs on
inappropriate queues, ACCVIOs, SHADDETINCON bugchecks,
and incorrect/inconsistent queue_fl and queue_bl pointers
in elements may occur.
o Excessive but allowable system process quota limits (PQL
parameters) can cause a shadow server process to be created
that is not able to perform the task for which it is intended,
specifically, shadow set copies and merges. Depending on
the system parameters, the process may exit or it may enter a
resource wait state and never transition to a useful state.
o Many I/Os that complete with errors have extraneous information
in the second longword of the IOST/IOSB. If the I/O is a data
transfer I/O, this may be interpreted as a transfer count.
Most products investigated see the error and ignore the transfer
count. However, there may be applications that interpret the
transfer count as "this many bytes processed before the error
occurred" which is incorrect.
o A system may crash with a REFCNTNEG bugcheck during shadow set
copy/merge operations.
o A system may crashes with an INVEXCEPTN bugcheck if a shadow set
member is write-protected and a write to that member is attempted.
o A node may hang due to no quorum after losing its connection to
the quorum disk.
o Layered drivers (e.g., Host-Based Raid) error recovery mechanisms
require the DUDRIVER interface to allow improved reliability.
o If a system disk is mounted in the cluster as a data disk and
a system is booted from a non-master member, the system will
crash with a SHADDETINCON crash in SHSB$READ_SCB.
o A SHADZEROMBR bugcheck may occur during an attempt to determine
if there is a valid source member of the shadow set that could
become the master.
o If an Alpha system disk is mounted on a different Alpha system
as a data disk and the first Alpha crashes and reboots more
than once, the Virtual Unit UCB$L_RWAITCNT field on the second
Alpha system will go negative. This will hang access to the
second Alpha's device.
o The system will crash with an ACCVIO in SHSB$CANCEL_IRP_CHEC
if a 'STOP PROCESS/ID=' command is issued to a process that
has IO outstanding to a shadow set.
o A shadowing crash may occur with the VCB address used as the
UCB address, when the shadow set has no member with the master
bit set in SHAD$B_MBR_STATUS.
o A system crash may occur when an attempt is made to mount
a write-protected source member.
Problems Addressed in ALPSHAD10_061:
o Sometimes a multiple member system disk shadow set does
not correctly complete a merge operation. The merge
is aborted but the shadow set is marked as though the
merge had completed. If the virtual unit does not exist
when the system is booted, this problem will not be
encountered.
o A SHADZEROMBR bugcheck can occur even though there are
valid source members in the shadow set.
INSTALLATION NOTES:
In order for the corrections in this kit to take effect, the system
must be rebooted. If the system is a member of a VMScluster, the
entire cluster should be rebooted.
This patch can be found at any of these sites:
Colorado Site
Georgia Site
Files on this server are as follows:
alpshad12_061.README
alpshad12_061.CHKSUM
alpshad12_061.CVRLET_TXT
alpshad12_061.a-dcx_axpexe
|