Type 3 protection
gop at us.ibm.com
Mon Nov 27 06:49:06 PST 2006
Formatted message: <A HREF="r0611270_f.htm">HTML-formatted message</A>
The rules for checking are in the footnotes. For example in table 71
footnote j describes the rules for checking the Reference Tag:
If type 1 protection is enabled, the device server checks the logical
block reference tag by comparing it to the lower 4 bytes of the LBA
associated with the logical block. If type 2 protection or type 3
protection is enabled, the device server checks the logical block
reference tag if it has knowledge of the contents of the LOGICAL BLOCK
REFERENCE TAG field. If type 2 protection is enabled, then this knowledge
may be acquired through the EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
field in a WRITE (32) command (see 5.29). If type 3 protection is enabled,
then the method for acquiring this knowledge is not defined by this
That footnote is telling you that for type 3 protection the target only
check the reference tag if the target knows what the content is be some
means not defined by the standard.
Also, sending out a message on this reflector that states the information
is "confidential information of Emulex Corporation" is a not a good way to
get responses. In the future any such messages received on my machine will
automatically be deleted.
Bye for now,
Dept 9A8 030-3 A410
E-Mail: gop at us.ibm.com
Gary.Franco at Emulex.Com
Sent by: owner-t10 at t10.org
11/25/2006 07:17 AM
<t10 at t10.org>
Type 3 protection
I would like a clarification on the correct implementation for Type 3
checking when dealing with WRPROTECT/RDPROTECT/VRPROTECT .
In SBC-3r07 clause 184.108.40.206 Type 3 protection states:
Type 3 protection:
a) defines the content of the LOGICAL BLOCK GUARD field within the
logical blocks of the data-in buffer and/or data-out buffer;
b) does not define the content of the LOGICAL BLOCK APPLICATION TAG
c) does not define the content of the LOGICAL BLOCK REFERENCE TAG
However in the individual command descriptors, WRITE(10) for example,
Table 71 ? WRPROTECT field indicates that both the Application Tag and
Reference Tag should be checked.
Since both of these DIF items are not defined for Type 3 protection, I
assume that for Type 3 protected devices these fields should not be
checked at all.
Can someone clarify?
Thanks in advance
Gary Franco Consultant Engineer
Emulex Network Systems
972-671-7433 Dallas Office
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