This bug is created as a clone of upstream ticket:
https://fedorahosted.org/freeipa/ticket/5334

This is not the first time I've had this occur, so I'm reporting it now.  One of my zones has stopped signing, and so for resolvers that validate DNSSEC (eg Google's public resolvers), the zone is effectively gone from the Internet.  Last time it happened I just resigned the zone and waited for the propagation delays, but given the time periods involved, and that it has happened again, I'd like to try and get it fixed - having zones missing for days on a semi-regular basis is not a tenable situation.

Below is the stack trace I get when ipa-dnskeysyncd tries to synchronize the zone:

{{{
Sep 30 20:04:19 dnsmaster.example.com ipa-dnskeysyncd[25797]: ipa.ipapython.dnssec.bindmgr.BINDMgr: INFO
Sep 30 20:04:19 dnsmaster.example.com ipa-dnskeysyncd[25797]: ipa.ipapython.dnssec.bindmgr.BINDMgr: INFO     Synchronizing zone example.com.
Sep 30 20:04:19 dnsmaster.example.com ipa-dnskeysyncd[25797]: ipa.ipapython.dnssec.bindmgr.BINDMgr: INFO     attrs: {'idnsseckeyref': ['pkcs11:object=hash1'], 'dn': 'cn=ZSK-20150531030418Z-hash1,cn=keys,idnsname=example.com.,cn=dns,dc=example,dc=com', 'cn': ['ZSK-20150531030418Z-hash1'], 'idnsseckeypublish': ['20150531030419Z'], 'objectclass': ['idnsSecKey'], 'idnssecalgorithm': ['RSASHA256'], 'idnsseckeyzone': ['TRUE'], 'idnsseckeycreated': ['20150531030418Z']}
Sep 30 20:04:19 dnsmaster.example.com python2[25797]: detected unhandled Python exception in '/usr/libexec/ipa/ipa-dnskeysyncd'
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: Traceback (most recent call last):
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/libexec/ipa/ipa-dnskeysyncd", line 112, in <module>
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: while ldap_connection.syncrepl_poll(all=1, msgid=ldap_search):
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib64/python2.7/site-packages/ldap/syncrepl.py", line 409, in syncrepl_poll
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: self.syncrepl_refreshdone()       
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib/python2.7/site-packages/ipapython/dnssec/keysyncer.py", line 115, in syncrepl_refreshdone
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: self.bindmgr.sync()               
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib/python2.7/site-packages/ipapython/dnssec/bindmgr.py", line 194, in sync
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: self.sync_zone(zone)              
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib/python2.7/site-packages/ipapython/dnssec/bindmgr.py", line 177, in sync_zone
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: self.install_key(zone, uuid, attrs, tempdir)
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib/python2.7/site-packages/ipapython/dnssec/bindmgr.py", line 113, in install_key
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: basename = ipautil.run(cmd)[0].strip()
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: File "/usr/lib/python2.7/site-packages/ipapython/ipautil.py", line 373, in run
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: raise CalledProcessError(p.returncode, arg_string, stdout)
Sep 30 20:04:20 dnsmaster.example.com ipa-dnskeysyncd[25797]: subprocess.CalledProcessError: Command ''/usr/sbin/dnssec-keyfromlabel-pkcs11' '-K' '/var/named/dyndb-ldap/ipa/master/example.com/tmpazgVEt' '-a' 'RSASHA256' '-l' 'pkcs11:object=hash1;pin-source=/var/lib/ipa/dnssec/softhsm_pin' '-P' '20150531030419' 'example.com.'' returned non-zero exit status 1
Sep 30 20:04:20 dnsmaster.example.com systemd[1]: ipa-dnskeysyncd.service: main process exited, code=exited, status=1/FAILURE
Sep 30 20:04:20 dnsmaster.example.com systemd[1]: Unit ipa-dnskeysyncd.service entered failed state.
Sep 30 20:04:20 dnsmaster.example.com systemd[1]: ipa-dnskeysyncd.service failed.
}}}

Please let me know what additional information I can provide.  This is a lesser-used domain, so I have a little leeway, but I would certainly appreciate any help that might be obtained in a timely fashion so it's not gone for too long.