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<DIV><SPAN class=050580518-24072007><FONT face="Palatino Linotype"
color=#0000ff><STRONG>Hi Hal,</STRONG></FONT></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG></SPAN> </DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>The code to find "duplicated" GUIDs stem from real user cases
where flawed </FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>burning procedure caused actual GUID duplications. There is
nothing "impossible". </FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><FONT face="Palatino Linotype"
color=#0000ff><STRONG>So it is really critical the the SM will be able to
recognize this case and abort.</STRONG></FONT></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG></SPAN> </DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>It might be that for testing someone wants to use a loopback plug
that cause the same </FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>port GUID appear on both sides of link - but it is better to
require the user doing the test </FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>to set some flag than to miss such a situation in real life
cluster.</FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG></SPAN> </DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>This requirement was written after many people wasted many hours
trying to figure out what was going on.</FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff>PLEASE DO NOT TAKE IT AWAY</FONT></STRONG></SPAN></DIV>
<DIV><SPAN class=050580518-24072007><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG></SPAN> </DIV><!-- Converted from text/rtf format -->
<P><SPAN lang=en-gb><B><I><FONT face="Monotype Corsiva" color=#0000ff
size=6>Eitan Zahavi</FONT></I></B><I></I></SPAN> <BR><SPAN lang=en-gb><FONT
face=Tahoma size=2>Senior Engineering Director, Software Architect</FONT></SPAN>
<BR><SPAN lang=en-gb><FONT face=Tahoma size=2>Mellanox Technologies
LTD</FONT></SPAN> <BR><SPAN lang=en-gb><FONT face=Tahoma
size=2>Tel:+972-4-9097208<BR>Fax:+972-4-9593245</FONT></SPAN> <BR><SPAN
lang=en-gb><FONT face=Tahoma size=2>P.O. Box 586 Yokneam 20692
ISRAEL</FONT></SPAN> </P>
<DIV> </DIV><BR>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
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<FONT face=Tahoma size=2><B>From:</B> Hal Rosenstock
[mailto:hal.rosenstock@gmail.com] <BR><B>Sent:</B> Tuesday, July 24, 2007 6:04
PM<BR><B>To:</B> Eitan Zahavi<BR><B>Cc:</B> OpenFabrics General; Sasha
Khapyorsky; Yevgeny Kliteynik<BR><B>Subject:</B> Re: OpenSM detection of
duplicated GUIDs on loopback<BR></FONT><BR></DIV>
<DIV></DIV><BR><BR>
<DIV><SPAN class=gmail_quote>On 7/24/07, <B class=gmail_sendername>Eitan
Zahavi</B> <<A
href="mailto:eitan@mellanox.co.il">eitan@mellanox.co.il</A>> wrote:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<DIV>
<DIV><FONT face=Tahoma size=2><SPAN class=q><B>From:</B> Hal Rosenstock
[mailto:<A onclick="return top.js.OpenExtLink(window,event,this)"
href="mailto:hal.rosenstock@gmail.com"
target=_blank>hal.rosenstock@gmail.com </A>] <BR></SPAN><B>Sent:</B>
Tuesday, July 24, 2007 5:53 PM<BR><B>To:</B> Eitan Zahavi<BR><B>Cc:</B>
OpenFabrics General; Sasha Khapyorsky; Yevgeny Kliteynik<BR><B>Subject:</B>
Re: OpenSM detection of duplicated GUIDs on loopback
<BR></FONT><BR> </DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV></DIV>Hi Eitan,<BR><BR>
<DIV><SPAN class=q><SPAN class=gmail_quote>On 7/24/07, <B
class=gmail_sendername>Eitan Zahavi</B> <<A
onclick="return top.js.OpenExtLink(window,event,this)"
href="mailto:eitan@mellanox.co.il" target=_blank>eitan@mellanox.co.il
</A>> wrote:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<DIV>
<DIV><SPAN><FONT face="Palatino Linotype" color=#0000ff><STRONG>Hi
Hal,</STRONG></FONT></SPAN></DIV>
<DIV><SPAN><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG></SPAN> </DIV>
<DIV><SPAN><STRONG><FONT face="Palatino Linotype" color=#0000ff>What is
this "loopback" connector used for?</FONT></STRONG></SPAN></DIV>
<DIV><SPAN><STRONG><FONT face="Palatino Linotype" color=#0000ff>Does not
seem to me like a very useful thing to
do.</FONT></STRONG></SPAN></DIV></DIV></BLOCKQUOTE>
<DIV><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG> </DIV>
<DIV>Perhaps not but no reason OpenSM can't handle this more
gracefully.</DIV><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<DIV>
<DIV><SPAN><STRONG><FONT face="Palatino Linotype" color=#0000ff>Anyway,
if it is not a production environment we could add a "debug mode" (-d
flag option) to ignore this
check.</FONT></STRONG></SPAN></DIV></DIV></BLOCKQUOTE>
<DIV><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG> </DIV></SPAN>
<DIV><SPAN class=q>Why would a separate flag be needed
?<BR></SPAN><SPAN><STRONG><FONT face="Palatino Linotype"
color=#0000ff>[EZ] Since I do not see any other solution for the SM
to know it is really a loop back plug rather then two devices with
same GUID connected back to back ...
</FONT></STRONG></SPAN></DIV></DIV></BLOCKQUOTE></DIV></BLOCKQUOTE>
<DIV>
<DIV> </DIV>
<DIV>"Technically", this should only occur when looped back and not two
devices with same GUID as GUID == globally unique and a duplication indicates
a "manufacturing" issue.</DIV>
<DIV> </DIV></DIV>
<DIV>Anyhow, can't these be treated the same (and handled more
gracefully) without an additional option/flag ?</DIV>
<DIV> </DIV>
<DIV>-- Hal</DIV><BR>
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<DIV>
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<DIV>
<DIV><SPAN class=e id=q_113f8b98c66c79db_7>
<DIV> </DIV>
<DIV>-- Hal</DIV><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<DIV>
<DIV><STRONG><FONT face="Palatino Linotype"
color=#0000ff></FONT></STRONG> </DIV>
<P><SPAN lang=en-gb><B><I><FONT face="Monotype Corsiva" color=#0000ff
size=6>Eitan Zahavi</FONT></I></B><I></I></SPAN> <BR><SPAN
lang=en-gb><FONT face=Tahoma size=2>Senior Engineering Director,
Software Architect </FONT></SPAN><BR><SPAN lang=en-gb><FONT face=Tahoma
size=2>Mellanox Technologies LTD</FONT></SPAN> <BR><SPAN
lang=en-gb><FONT face=Tahoma
size=2>Tel:+972-4-9097208<BR>Fax:+972-4-9593245</FONT></SPAN> <BR><SPAN
lang=en-gb><FONT face=Tahoma size=2>P.O. Box 586 Yokneam 20692
ISRAEL</FONT></SPAN> </P>
<DIV> </DIV><BR>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV lang=en-us dir=ltr align=left>
<HR>
<FONT face=Tahoma size=2><B>From:</B> Hal Rosenstock [mailto:<A
onclick="return top.js.OpenExtLink(window,event,this)"
href="mailto:hal.rosenstock@gmail.com"
target=_blank>hal.rosenstock@gmail.com</A>] <BR><B>Sent: </B>Tuesday,
July 24, 2007 5:31 PM<BR><B>To:</B> OpenFabrics General<BR><B>Cc:</B>
Sasha Khapyorsky; Eitan Zahavi; Yevgeny
Kliteynik<SPAN><BR><B>Subject:</B> OpenSM detection of duplicated
GUIDs on loopback<BR></SPAN></FONT><BR> </DIV>
<DIV><SPAN>
<DIV></DIV>
<DIV>Hi,</DIV>
<DIV> </DIV>
<DIV>This is what starts off as a "minor" issue and I know it has been
discussed it somewhat in the past: </DIV>
<DIV> </DIV>
<DIV>Putting a loopback connector on a (switch) link causes OpenSM to
indicate duplicated GUID error 0D18 as
follows:<BR><BR>__osm_ni_rcv_set_links<BR>{<BR>...<BR>
/*<BR>
When there are only two nodes with exact same guids (connected back
<BR>
to back) - the previous check for duplicated guid will not
catch<BR>
them. But the link will be from the port to
itself...<BR>
Enhanced Port 0 is an exception to
this<BR> */
<BR> if
((osm_node_get_node_guid( p_node ) == p_ni_context->node_guid)
&&<BR>
(port_num == p_ni_context->port_num)
&&<BR>
(port_num !=
0))<BR>
{<BR>
osm_log( p_rcv->p_log, OSM_LOG_ERROR,
<BR>
"__osm_ni_rcv_set_links: ERR 0D18:
"<BR>
"Duplicate GUID found by link from a port to
itself:"<BR>
"node 0x%" PRIx64 ", port number 0x%X\n",
<BR>
cl_ntoh64( osm_node_get_node_guid( p_node )
),<BR>
port_num );<BR>...<BR><BR>So this occurs over and over and over and
fills the log with the same spew. This should be improved IMO.
<BR><BR>Is this really a fatal condition ? Doesn't seem like it should
be to me. </DIV>
<DIV> </DIV>
<DIV>Also, OpenSM can "ride" this out with -y (stay on fatal) but is
that safe for this condition ?</DIV>
<DIV> </DIV>
<DIV>Seems like something like an extra loopback bit should be
added to some port structure which should cause these links to be
ignored. This bit would then be reset when the peer is now longer
itself. <BR><BR>Also, is there a relationship of this with the
12x/duplicated GUID code ? </DIV>
<DIV> </DIV>
<DIV>Thanks.</DIV>
<DIV> </DIV>
<DIV>--
Hal<SPAN></SPAN></DIV></SPAN></DIV></BLOCKQUOTE></DIV></BLOCKQUOTE></SPAN></DIV></DIV><BR></BLOCKQUOTE></DIV></BLOCKQUOTE></DIV><BR></BLOCKQUOTE></BODY></HTML>