Trove and panko port conflict

I use RDO installed Trove and panko,When I restart httpd,found someting:

# systemctl restart httpd
Job for httpd.service failed because the control process exited with error code. See "systemctl status httpd.service" and "journalctl -xe" for details.

# systemctl status httpd.service
● httpd.service - The Apache HTTP Server
   Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
  Drop-In: /usr/lib/systemd/system/httpd.service.d
           └─openstack-dashboard.conf
   Active: failed (Result: exit-code) since Fri 2017-07-21 15:51:25 CST; 28s ago
  Process: 5892 ExecStop=/bin/kill -WINCH ${MAINPID} (code=exited, status=1/FAILURE)
  Process: 5889 ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND (code=exited, status=1/FAILURE)
  Process: 5781 ExecStartPre=/usr/bin/python /usr/share/openstack-dashboard/manage.py compress --force -v0 (code=exited, status=0/SUCCESS)
  Process: 5757 ExecStartPre=/usr/bin/python /usr/share/openstack-dashboard/manage.py collectstatic --noinput --clear -v0 (code=exited, status=0/SUCCESS)
 Main PID: 5889 (code=exited, status=1/FAILURE)

Jul 21 15:51:25 ocata01 httpd[5889]: (98)Address already in use: AH00072: make_sock: could not bind to address [::]:8779
Jul 21 15:51:25 ocata01 httpd[5889]: (98)Address already in use: AH00072: make_sock: could not bind to address 0.0.0.0:8779
Jul 21 15:51:25 ocata01 httpd[5889]: no listening sockets available, shutting down
Jul 21 15:51:25 ocata01 httpd[5889]: AH00015: Unable to open logs
Jul 21 15:51:25 ocata01 systemd[1]: httpd.service: main process exited, code=exited, status=1/FAILURE
Jul 21 15:51:25 ocata01 kill[5892]: kill: cannot find process ""
Jul 21 15:51:25 ocata01 systemd[1]: httpd.service: control process exited, code=exited status=1
Jul 21 15:51:25 ocata01 systemd[1]: Failed to start The Apache HTTP Server.
Jul 21 15:51:25 ocata01 systemd[1]: Unit httpd.service entered failed state.
Jul 21 15:51:25 ocata01 systemd[1]: httpd.service failed.

# netstat -tnlp|grep 8779
tcp 0 0 0.0.0.0:8779 0.0.0.0:* LISTEN 5706/python2

# ps -ef|grep 5706
trove 5706 1 2 15:50 ? 00:00:02 /usr/bin/python2 /usr/bin/trove-api
trove 5728 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5729 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5730 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5731 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5732 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5733 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5734 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
trove 5735 5706 0 15:50 ? 00:00:00 /usr/bin/python2 /usr/bin/trove-api
root 6149 1694 0 15:52 pts/0 00:00:00 grep --color=auto 5706

when i stoped trove-api,i can restart httpd success

# systemctl stop openstack-trove-api.service
# systemctl restart httpd
# systemctl status httpd|grep Active
   Active: active (running) since Fri 2017-07-21 15:53:57 CST; 53s ago

# netstat -tnlp|grep 8779
tcp6 0 0 :::8779 :::* LISTEN 6467/httpd

why httpd used 8779 port ?

# egrep -r 8779 /etc/httpd/*
/etc/httpd/conf/ports.conf:Listen 8779
/etc/httpd/conf.d/10-panko_wsgi.conf:<VirtualHost *:8779>

I found panko used port 8779.

# openstack endpoint list |grep 8779
| 13ba084cba874aeeb9344638a1621c6f | RegionOne | trove | database | True | internal | http://172.28.11.214:8779/v1.0/%(tenant_id)s |
| 26287563c191453f9b442df06618da0f | RegionOne | trove | database | True | public | http://172.28.11.214:8779/v1.0/%(tenant_id)s |
| 48e0a4321cb3429481ee25257daf86bb | RegionOne | panko | event | True | internal | http://172.28.11.214:8779 |
| 56253953e76743158654e8783a40c548 | RegionOne | panko | event | True | public | http://172.28.11.214:8779 |
| 7f5296b6a3974fe2b5ff12cc92ad8c77 | RegionOne | panko | event | True | admin | http://172.28.11.214:8779 |
| 9dde838a68254dc0ab46a67b7b6fd458 | RegionOne | trove | database | True | admin | http://172.28.11.214:8779/v1.0/%(tenant_id)s |