Description of problem:
in customers with high number of logins/kinit's we are seeing lots of MOD operations of attribute krbLastSuccessfulAuth.
Even if this attribute is skipped in fractional replication, all the changes are sent to changelog and replication has to browse them to decide whether to skip or not.
Combined with bug
this could easily provoke replicas locked and very important delay in replication. Even once that former bug will be fixed, it could be useful not to keep that information that Alexander (thanks !) checked is not used in ipa context.
There is already a way to disable this attribute by:
ldapmodify -x -D "cn=directory manager" -W <<EOF
ipaConfigString: KDC:Disable Last Success
(special thanks to Marc Sauton!)
We would like, if possible, to have this behavior set by default in IPA.
The question in that RFE is to know if it is useful or not to update bound entry at each bind.
This systematic update reveal a performance issue on fraction replication BUT by design there was a DS potential performance issue. (independently of that specific systematic update of krbLastSuccessfulAuth)
To address this issue there were several possibilities.
- The one that was implemented was https://pagure.io/389-ds-base/issue/48266 (https://bugzilla.redhat.com/show_bug.cgi?id=1259949).
This ticket is fixed since 389-ds-base-18.104.22.168-18.el7.
- The ticket https://pagure.io/389-ds-base/issue/48286, was another possibility to workaround the DS bug. Preventing logging in replication CL some attributes. It is not yet implement and we do not know if it will.
so since 389-ds-base-22.214.171.124-18.el7 there is no more DS fractional replication performance issue.
It remains the question if updating bound entry is useful or not (this RFE). If it is not useful, IMHO it is easier to fix it in IPA (ipaConfigString: KDC:Disable Last Success) rather than asking for the fix https://pagure.io/389-ds-base/issue/48286 and configure DS to not log some attribute in CL.
Verified on ipa-server-4.5.0-13.el7:
# ipactl status
Directory Service: RUNNING
krb5kdc Service: RUNNING
kadmin Service: RUNNING
named Service: RUNNING
httpd Service: RUNNING
ipa-custodia Service: RUNNING
ntpd Service: RUNNING
pki-tomcatd Service: RUNNING
ipa-otpd Service: RUNNING
ipa-dnskeysyncd Service: RUNNING
ipa: INFO: The ipactl command was successful
# ipa config-show
Maximum username length: 32
Home directory base: /home
Default shell: /bin/sh
Default users group: ipausers
Default e-mail domain: testrelm.test
Search time limit: 2
Search size limit: 100
User search fields: uid,givenname,sn,telephonenumber,ou,title
Group search fields: cn,description
Enable migration mode: FALSE
Certificate Subject base: O=TESTRELM.TEST
Password Expiration Notification (days): 4
Password plugin features: AllowNThash, KDC:Disable Last Success
SELinux user map order: guest_u:s0$xguest_u:s0$user_u:s0$staff_u:s0-s0:c0.c1023$unconfined_u:s0-s0:c0.c1023
Default SELinux user: unconfined_u:s0-s0:c0.c1023
Default PAC types: MS-PAC, nfs:NONE
IPA masters: host-8-178-58.testrelm.test
IPA CA servers: host-8-178-58.testrelm.test
IPA NTP servers: host-8-178-58.testrelm.test
IPA CA renewal master: host-8-178-58.testrelm.test
Please note that Red Hat officially released public RHEL-7.4 Beta this week, as announced here:
The new RHEL-7.4 release includes a lot of new IdM functionality, including this RFE. Highlights can be found in RHEL-7.4 Release Notes, especially in the Authentication & Interoperability chapter:
IdM Engineering team would like to encourage everyone interested in this new functionality (and especially customers or community members requesting it) to try Beta and provide us with your feedback!
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.