[Freeipa-users] ns-slapd hangs for 2-3 minutes, then resumes.

Mon Jun 13 19:13:34 UTC 2016

Hi Rich,

After I started running the stack traces, the problem hasn't happen as
frequently as it use to but today I was able to get the stack traces.
As they aren't similar I'll send them over to you in a separate email.

This is what I did to start the stack traces (CentOS 7):
# yum install -y --enablerepo=base-debuginfo 389-ds-base-debuginfo
ipa-debuginfo slapi-nis-debuginfo nspr-debuginfo
# yum install -y gdb
# systemctl stop ipa.service ; sleep 10; systemctl start ipa.service
# mkdir -p /var/log/stacktraces

Setup crontab to run the following every minute:
gdb -ex 'set confirm off' -ex 'set pagination off' -ex 'thread apply
all bt full' -ex 'quit' /usr/sbin/ns-slapd `pidof ns-slapd` >
/var/log/stacktraces/stacktrace.`date +%s`.txt 2>&1

Thank you so much for your help,

Guillermo

On Wed, Jun 1, 2016 at 6:52 PM, Guillermo Fuentes
<guillermo.fuentes at modernizingmedicine.com> wrote:
> I'm now taking stack traces every minute and waiting for it to hang
> again to check it. It happens usually under load but it's
> unpredictable. Must likely tomorrow.
> GUILLERMO FUENTES
> SR. SYSTEMS ADMINISTRATOR
>
> 561-880-2998 x1337
>
> guillermo.fuentes at modmed.com
>
>
>
>
>
>
> On Wed, Jun 1, 2016 at 2:03 PM, Rich Megginson <rmeggins at redhat.com> wrote:
>> On 06/01/2016 10:37 AM, Guillermo Fuentes wrote:
>>>
>>> Hi all,
>>>
>>> We are experiencing a similar issue like the one discussed in the
>>> following thread but we are running FreeIPA 4.2 on CentOS 7.2:
>>> https://www.redhat.com/archives/freeipa-users/2015-February/msg00205.html
>>
>>
>> Are your stack traces similar?
>>
>>
>>>
>>> LDAP service stops responding to queries (hangs). LDAP connections on
>>> the server climb sometimes up to 10 times the normal amount and load
>>> goes to 0. Then, the connections start to drop until they get to a
>>> normal level and the LDAP service starts to respond to queries again.
>>> This happens in between 3-5 minutes:
>>>
>>> Time,LDAP conn, Opened files(ns-slapd), File
>>> Desc(ns-slapd),Threads(ns-slapd),Load1,Load5,Load15
>>> 8:54:03,101,353,216,142,0.43,0.20,0.16
>>> 8:55:02,108,359,221,142,0.19,0.18,0.15
>>> 8:56:03,110,361,224,142,0.07,0.15,0.14
>>> 8:57:14,117,383,246,142,0.15,0.16,0.15
>>> 8:58:04,276,371,234,142,0.05,0.13,0.14
>>> 8:59:05,469,371,234,142,0.02,0.11,0.13
>>> 9:00:08,719,371,234,142,0.01,0.09,0.12
>>> 9:01:18,1060,371,234,142,0.00,0.07,0.12
>>> 9:02:10,742,371,233,142,0.10,0.09,0.12
>>> 9:03:06,365,372,235,142,0.13,0.10,0.13
>>> 9:04:04,262,379,242,142,0.87,0.29,0.19
>>> 9:05:02,129,371,233,142,0.51,0.31,0.20
>>> 9:06:03,126,377,240,142,0.42,0.33,0.22
>>> 9:07:03,125,377,238,142,0.17,0.27,0.21
>>>
>>> Nothing is logged in the errors log file of the server having the
>>> problem (ipa1 as an example).
>>> In the replicas this is logged:
>>> 8:59:05 -0400] NSMMReplicationPlugin - agmt="cn=meToipa1.example.com"
>>> (ipa1:389): Unable to receive the response for a startReplication
>>> extended operation to consumer (Timed out). Will retry later.
>>> 9:01:05 -0400] NSMMReplicationPlugin - agmt="cn=meToipa1.example.com"
>>> (ipa1:389): Unable to receive the response for a startReplication
>>> extended operation to consumer (Timed out). Will retry later.
>>>
>>> Nothing is logged in the access log file until after ns-slapd starts
>>> responding again:
>>> ...
>>> 8:57:00 -0400] conn=12384 fd=234 slot=234 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 8:57:00 -0400] conn=12385 fd=235 slot=235 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 8:57:00 -0400] conn=12386 fd=236 slot=236 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 8:57:00 -0400] conn=12387 fd=237 slot=237 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 8:57:00 -0400] conn=10384 op=1227 EXT oid="2.16.840.1.113730.3.5.12"
>>> name="replication-multimaster-extop"
>>> 8:57:00 -0400] conn=12324 op=8 RESULT err=0 tag=101 nentries=1 etime=0
>>> 8:57:00 -0400] conn=8838 op=2545 EXT oid="2.16.840.1.113730.3.5.12"
>>> name="replication-multimaster-extop"
>>> 8:57:00 -0400] conn=8838 op=2545 RESULT err=0 tag=120 nentries=0 etime=0
>>> 8:57:00 -0400] conn=10384 op=1227 RESULT err=0 tag=120 nentries=0 etime=0
>>> 8:57:00 -0400] conn=12382 op=-1 fd=170 closed - B1
>>> 8:57:00 -0400] conn=12383 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 8:57:00 -0400] conn=12384 op=-1 fd=234 closed - B1
>>> 8:57:00 -0400] conn=12385 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 8:57:00 -0400] conn=12383 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 8:57:00 -0400] conn=12386 op=-1 fd=236 closed - B1
>>> 8:57:00 -0400] conn=12385 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 8:57:00 -0400] conn=12387 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 8:57:00 -0400] conn=12387 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 8:57:00 -0400] conn=12385 op=1 BIND dn="" method=sasl version=3
>>> mech=GSSAPI
>>> 8:57:00 -0400] conn=12387 op=1 BIND dn="" method=sasl version=3
>>> mech=GSSAPI
>>> 8:57:00 -0400] conn=12385 op=1 RESULT err=14 tag=97 nentries=0
>>> etime=0, SASL bind in progress
>>> 8:57:00 -0400] conn=12383 op=1 BIND dn="" method=sasl version=3
>>> mech=GSSAPI
>>> 8:57:00 -0400] conn=10384 op=1228 EXT oid="2.16.840.1.113730.3.5.5"
>>> name="Netscape Replication End Session"
>>> 8:57:00 -0400] conn=10384 op=1228 RESULT err=0 tag=120 nentries=0 etime=0
>>> 8:57:00 -0400] conn=12383 op=1 RESULT err=14 tag=97 nentries=0
>>> etime=0, SASL bind in progress
>>> 9:02:00 -0400] conn=12388 fd=170 slot=170 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12389 fd=234 slot=234 SSL connection from
>>> 172.20.0.24 to 172.20.2.45
>>> 9:02:00 -0400] conn=12390 fd=236 slot=236 connection from local to
>>> /var/run/slapd-EXAMPLE-COM.socket
>>> 9:02:00 -0400] conn=12391 fd=238 slot=238 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12392 fd=239 slot=239 SSL connection from
>>> 172.20.0.24 to 172.20.2.45
>>> 9:02:00 -0400] conn=12393 fd=240 slot=240 connection from local to
>>> /var/run/slapd-EXAMPLE-COM.socket
>>> 9:02:00 -0400] conn=12394 fd=241 slot=241 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12395 fd=242 slot=242 SSL connection from
>>> 172.20.0.24 to 172.20.2.45
>>> 9:02:00 -0400] conn=12396 fd=243 slot=243 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12397 fd=244 slot=244 SSL connection from
>>> 172.20.0.24 to 172.20.2.45
>>> 9:02:00 -0400] conn=12398 fd=245 slot=245 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12400 fd=247 slot=247 connection from 172.20.0.1
>>> to 172.20.2.45
>>> 9:02:00 -0400] conn=12401 fd=248 slot=248 connection from 172.20.0.1
>>> to 172.20.2.45
>>> ...
>>> 9:02:00 -0400] conn=12390 op=0 BIND dn="" method=sasl version=3
>>> mech=GSSAPI
>>> 9:02:00 -0400] conn=12388 op=-1 fd=170 closed - B1
>>> 9:02:00 -0400] conn=12393 op=0 BIND dn="" method=sasl version=3
>>> mech=GSSAPI
>>> 9:02:00 -0400] conn=12391 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 9:02:00 -0400] conn=12394 op=-1 fd=241 closed - B1
>>> 9:02:00 -0400] conn=12391 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 9:02:00 -0400] conn=12396 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 9:02:00 -0400] conn=12396 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 9:02:00 -0400] conn=12398 op=-1 fd=245 closed - B1
>>> 9:02:00 -0400] conn=12400 op=0 SRCH base="" scope=0
>>> filter="(objectClass=*)" attrs="supportedSASLMechanisms
>>> defaultnamingcontext namingContexts schemanamingcontext saslrealm"
>>> 9:02:00 -0400] conn=12400 op=0 RESULT err=0 tag=101 nentries=1 etime=0
>>> 9:02:00 -0400] conn=12401 op=-1 fd=248 closed - B1
>>> 9:02:00 -0400] conn=12391 op=1 ABANDON targetop=NOTFOUND msgid=1
>>> 9:02:00 -0400] conn=12396 op=1 ABANDON targetop=NOTFOUND msgid=1
>>> 9:02:00 -0400] conn=12400 op=1 ABANDON targetop=NOTFOUND msgid=1
>>> 9:02:00 -0400] conn=12391 op=2 UNBIND
>>> 9:02:00 -0400] conn=12396 op=2 UNBIND
>>> 9:02:00 -0400] conn=12391 op=2 fd=238 closed - U1
>>> 9:02:00 -0400] conn=12396 op=2 fd=243 closed - U1
>>> 9:02:00 -0400] conn=12400 op=2 UNBIND
>>> 9:02:00 -0400] conn=12400 op=2 fd=247 closed - U1
>>> ...
>>>
>>>
>>> Environment:
>>> # cat /etc/redhat-release
>>> CentOS Linux release 7.2.1511 (Core)
>>>
>>> # rpm -qa ipa*
>>> ipa-server-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>> ipa-python-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>> ipa-admintools-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>> ipa-server-trust-ad-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>> ipa-client-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>> ipa-server-dns-4.2.0-15.0.1.el7.centos.6.1.x86_64
>>>
>>> # rpm -qa 389*
>>> 389-ds-base-libs-1.3.4.0-30.el7_2.x86_64
>>> 389-ds-base-1.3.4.0-30.el7_2.x86_64
>>>
>>> We have 4 FreeIPA servers with replication working fine between them.
>>> ipa1 is handling LDAP authentication for +400 clients and has been
>>> tunned as recommended per
>>>
>>> https://access.redhat.com/documentation/en-US/Red_Hat_Directory_Server/8.2/html/Performance_Tuning_Guide/system-tuning.html
>>>
>>> Is this a known issue?
>>> Any idea what can be causing ns-slapd to hang?
>>>
>>> Thanks in advance!
>>>
>>> Guillermo
>>>
>>
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