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<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006>Hi,</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN class=165060811-17102006>Let
me first explain why the current OFED release does not support SRP-HA on
RHEL4.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006>SRP-HA is using Device Mapper
multipath.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006>Multipath prerequisites include udev of higher version
than 050.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006>RHEL4 distributions includes udev 039. udev is an
important part of the distribution and I do not think that users will be ready
to upgrade it in order to have SRP-HA.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN class=165060811-17102006>To
my best knowledge the main reason that multipath needs at least udev 050 is
because it uses the RUN option (This option executes its given parameter after
the device exist). Multipath uses the RUN option to execute kpartx
that handles the partitions of the new device. SRP-HA also uses the RUN
option to execute the multipath command.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN class=165060811-17102006>I
have an idea on how to overcome this problem. I want to implement a
srp-multipath-daemon. This daemon will get kpartx and multipath requests using a
shared message queue. The udev will use the PROGRAM option (That executes its
given parameter immediately - before the device exist) to post request to this
shared message queue and return immediately. The daemon will wait for the device
to create and only than it will execute the commands.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN class=165060811-17102006>In
any case this technique will not be a part of the coming OFED
release.</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006>Ishai</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"><SPAN
class=165060811-17102006></SPAN></SPAN> </P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Tahoma><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"></SPAN></FONT> </P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Tahoma><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">-----Original
Message-----<BR><B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Sharma,
Karun [mailto:ksharma@silverstorm.com] <BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Tuesday, October 17, 2006 5:11
AM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> Tziporet Koren; Open
Fabrics<BR><B><SPAN style="FONT-WEIGHT: bold">Cc:</SPAN></B> openib<BR><B><SPAN
style="FONT-WEIGHT: bold">Subject:</SPAN></B> RE: [openfabrics-ewg] OFED 1.1
release schedule</SPAN></FONT></P>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face="Times New Roman"
size=3><SPAN style="FONT-SIZE: 12pt"></SPAN></FONT> </P>
<DIV id=idOWAReplyText72564>
<DIV>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial">The plan is OK with
Silverstorm.</SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I have a question though. What
are the plans to support SRP-HA feature on RHEL4 kernels
?</SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face="Times New Roman"
size=3><SPAN style="FONT-SIZE: 12pt"></SPAN></FONT> </P></DIV>
<DIV>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Thanks</SPAN></FONT></P></DIV>
<DIV>
<P class=MsoNormal style="MARGIN-LEFT: 0.5in"><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Karun</SPAN></FONT></P></DIV></DIV></FONT></DIV></BODY></HTML>