<html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> <div class="moz-cite-prefix">On 11/21/2014 10:59 AM, <a class="moz-txt-link-abbreviated" href="mailto:dbischof@hrz.uni-kassel.de">dbischof@hrz.uni-kassel.de</a> wrote: </div> <blockquote cite="mid:alpine.LSU.2.11.1411211033510.1449@fred" type="cite">Hi, On Thu, 20 Nov 2014, thierry bordaz wrote: <blockquote type="cite">On 11/20/2014 12:03 PM, <a class="moz-txt-link-abbreviated" href="mailto:dbischof@hrz.uni-kassel.de">dbischof@hrz.uni-kassel.de</a> wrote: <blockquote type="cite"> On Thu, 20 Nov 2014, thierry bordaz wrote: <blockquote type="cite">Server1 successfully replicated to Server2, but Server2 fails to replicated to Server1. The replication Server2->Server1 is done with kerberos authentication. Server1 receives the replication session, successfully identify the replication manager, start to receives replication extop but suddenly closes the connection. [19/Nov/2014:14:21:39 +0100] conn=2980 fd=78 slot=78 connection from xxx to yyy [19/Nov/2014:14:21:39 +0100] conn=2980 op=0 BIND dn="" method=sasl version=3 mech=GSSAPI [19/Nov/2014:14:21:39 +0100] conn=2980 op=0 RESULT err=14 tag=97 nentries=0 etime=0, SASL bind in progress [19/Nov/2014:14:21:39 +0100] conn=2980 op=1 BIND dn="" method=sasl version=3 mech=GSSAPI [19/Nov/2014:14:21:39 +0100] conn=2980 op=1 RESULT err=14 tag=97 nentries=0 etime=0, SASL bind in progress [19/Nov/2014:14:21:39 +0100] conn=2980 op=2 BIND dn="" method=sasl version=3 mech=GSSAPI [19/Nov/2014:14:21:39 +0100] conn=2980 op=2 RESULT err=0 tag=97 nentries=0 etime=0 dn="krbprincipalname=xxx" [19/Nov/2014:14:21:39 +0100] conn=2980 op=3 SRCH base="" scope=0 filter="(objectClass=*)" attrs="supportedControl supportedExtension" [19/Nov/2014:14:21:39 +0100] conn=2980 op=3 RESULT err=0 tag=101 nentries=1 etime=0 [19/Nov/2014:14:21:39 +0100] conn=2980 op=4 SRCH base="" scope=0 filter="(objectClass=*)" attrs="supportedControl supportedExtension" [19/Nov/2014:14:21:39 +0100] conn=2980 op=4 RESULT err=0 tag=101 nentries=1 etime=0 [19/Nov/2014:14:21:39 +0100] conn=2980 op=5 EXT oid="2.16.840.1.113730.3.5.12" name="replication-multimaster-extop" [19/Nov/2014:14:21:39 +0100] conn=2980 op=5 RESULT err=0 tag=120 nentries=0 etime=0 [19/Nov/2014:14:21:39 +0100] conn=2980 op=6 SRCH base="cn=schema" scope=0 filter="(objectClass=*)" attrs="nsSchemaCSN" [19/Nov/2014:14:21:39 +0100] conn=2980 op=6 RESULT err=0 tag=101 nentries=1 etime=0 [19/Nov/2014:14:21:39 +0100] conn=2980 op=-1 fd=78 closed - I/O function error. The reason of this closure is logged in server1 error log. sasl_decode fails to decode a received PDU. [19/Nov/2014:14:21:39 +0100] - sasl_io_recv failed to decode packet for connection 2980 I do not know why it fails but I wonder if the received PDU is not larger than the maximum configured value. The attribute nsslapd-maxsasliosize is set to 2Mb by default. Would it be possible to increase its value (5Mb) to see if it has an impact [...] </blockquote> I set nsslapd-maxsasliosize to 6164480 on both machines, but the problem remains. </blockquote> The sasl-decode fails but the exact returned value is not logged. With standard version we may need to attach a debugger and then set a conditional breakpoint in sasl-decode just after conn->oparams.decode that will fire if result !=0. Now this can change the dynamic and possibly prevent the problem to occur again. The other option is to use an instrumented version to log this value. </blockquote> If I understand the mechanism correctly, Server1 needs to have debug versions of the relevant packages (probably 389-ds-base and cyrus-sasl) installed in order to track down the problem. Unfortunately, my Server1 is in production use - if I break it, my colleagues will grab forks and torches and be after me. A short downtime would be ok, though. Is there something else I could do? </blockquote> Hello, Sure I do not want to trigger so much trouble ;-) I think my email was not clear. To go further we would need to know the exact reason why sasl_decode fails. I see two options: <ul> <li>Prepare a debug version, that would report in the error logs the returned valud of sasl_decode (when it fails). Except downtime to install the debug version, it has no impact in production. </li> <li>Do a debug session (gdb) on Server1. The debug session will install a breakpoint at a specific place, let the server run, catch the sasl_decode failure and note the return code, exit from debugger. When the problem occurs, it happens regularly (each 5 seconds) so we should not have to wait long. That means that debugging Server1 should disturb production for 5 to 10 min. A detailed procedure to do the debug session is required. </li> </ul> thanks thierry <blockquote cite="mid:alpine.LSU.2.11.1411211033510.1449@fred" type="cite"> Mit freundlichen Gruessen/With best regards, --Daniel. </blockquote> </body> </html>