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<p><font size="2" face="sans-serif">Hello,</font><br>
<br>
<font size="2" face="sans-serif">I am seeing a problem with running my code using CORBA (omniORB - 4.1.4) on a RHEL 6.1 system. </font><br>
<br>
<font size="2" face="sans-serif">Problem scenario is this:</font><br>
<br>
<font size="2" face="sans-serif">1.) invoke the CORBA request </font><br>
<font size="2" face="sans-serif">2.) this causes a LOCATE_REQUEST to be sent out</font><br>
<font size="2" face="sans-serif">3.) TCP ACK is sent back</font><br>
<font size="2" face="sans-serif"> Note: looking through the CORBA server traces. this LOCATE_REQUEST is never received there. However, a suspicious looking</font><br>
<font size="2" face="sans-serif"> one is received in its place.</font><br>
<font size="2" face="sans-serif">4.) but no LOCATE_REPLY is sent back</font><br>
<font size="2" face="sans-serif">5.) then after a while (looks like a 3 minute time-out), the LOCATE_REQUEST is sent out again. (on a different port)</font><br>
<font size="2" face="sans-serif">6.) this time the LOCATE_REPLY is sent back.</font><br>
<br>
<font size="2" face="sans-serif">======================= relevant TCPdump results ==================</font><br>
<font size="2" face="sans-serif">349 18.856754 9.5.167.92 9.5.167.92 GIOP GIOP 1.2 LocateRequest s=26 id=20 op=LocateRequest</font><br>
<font size="2" face="sans-serif">0000 00 00 00 00 00 00 00 00 00 00 00 00 08 00 45 00 ........ ......E.</font><br>
<font size="2" face="sans-serif">0010 00 5a 68 92 40 00 40 06 71 49 09 05 a7 5c 09 05 .Zh.@.@. qI...\..</font><br>
<font size="2" face="sans-serif">0020 a7 5c cf d6 8c d5 3c 86 94 47 3c 63 0b b9 80 18 .\....<. .G<c....</font><br>
<font size="2" face="sans-serif">0030 01 09 61 0f 00 00 01 01 08 0a 14 1a e9 34 14 1a ..a..... .....4..</font><br>
<font size="2" face="sans-serif">0040 e7 3b 47 49 4f 50 01 02 01 03 1a 00 00 00 14 00 .;GIOP.. ........</font><br>
<font size="2" face="sans-serif">0050 00 00 00 00 00 00 0e 00 00 00 fe ea 91 66 4e 00 ........ .....fN.</font><br>
<font size="2" face="sans-serif">0060 00 37 53 00 00 00 00 00 .7S..... </font><br>
<br>
<font size="2" face="sans-serif">350 18.856783 9.5.167.92 9.5.167.92 TCP 36053 > 53206 [ACK] Seq=299 Ack=1469 Win=38144 Len=0 TSV=337307956 TSER=337307956</font><br>
<font size="2" face="sans-serif">0000 00 00 00 00 00 00 00 00 00 00 00 00 08 00 45 00 ........ ......E.</font><br>
<font size="2" face="sans-serif">0010 00 34 ec c5 40 00 40 06 ed 3b 09 05 a7 5c 09 05 .4..@.@. .;...\..</font><br>
<font size="2" face="sans-serif">0020 a7 5c 8c d5 cf d6 3c 63 0b b9 3c 86 94 6d 80 10 .\....<c ..<..m..</font><br>
<font size="2" face="sans-serif">0030 01 2a a4 76 00 00 01 01 08 0a 14 1a e9 34 14 1a .*.v.... .....4..</font><br>
<font size="2" face="sans-serif">0040 e9 34 .4 </font><br>
<br>
<font size="2" face="sans-serif">// Locate_Reply never is sent.</font><br>
<br>
<font size="2" face="sans-serif">****** Also, the suspect GIOP message shown below in the CORBA trace never appears in the TCP tracelog.</font><br>
<br>
<font size="2" face="sans-serif">============== CORBA server-side daemon trace ===================</font><br>
<font size="2" face="sans-serif">taken around the time that the Locate_Request is expected to be received.</font><br>
<br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:52.667839: SocketCollection idle. Sleeping.</font><br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:52.670531: inputMessage: from giop:tcp:[::ffff:9.5.167.92]:53206 38 bytes</font><br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:52.670551: </font><br>
<font size="2" face="sans-serif">4749 4f50 0102 0100 0501 0000 1200 0000 GIOP............</font><br>
<font size="2" face="sans-serif">0000 0000 0000 0000 0e00 0000 feea 9166 ...............f</font><br>
<font size="2" face="sans-serif">4e00 0037 5300 N..7S.</font><br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:55.919786: Scan for idle connections (1315344895,919689000)</font><br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:55.919816: Scavenger reduce idle count for strand 0x7f70f80009b0 to 35</font><br>
<font size="2" face="sans-serif">omniORB: 2011-09-06 16:34:55.919840: Scavenger reduce idle count for strand 0x7f70f80016b0 to 35</font><br>
<br>
<font size="2" face="sans-serif">Does this Message look suspicious?</font><br>
<br>
<font size="2" face="sans-serif">This problem is very consistent. Full traces are easily available. </font><br>
<br>
<font size="2" face="sans-serif">This test runs successfully everytime on RHEL 5.5 system, but fails everytime on a RHEL 6.1 system. (Should qualify this some, in that machine type also is important here. It fails everytime on a RHEL 6.1 / HS21 IBM bladesystem but works everytime on RHEL 6.1 / HS22 IBM bladesystem. This behavior has been verified on several machines of the various types, & was very consistent.)</font><br>
<br>
<font size="2" face="sans-serif">Best Regards,<br>
<br>
Brad Fawcett<br>
bfawcett@us.ibm.com </font></body></html>