Renaming DNS zones often results in an Exception being thrown

Description

Renaming a DNS zone where hosts have been added results in an exception and leaves the zone with multiple zoneName attributes.

Distribution Name and Version

Ubuntu 16.04

FusionDirectory Version

1.2.1

Plugin with the defect

dns

PHP version used

7.0.22

Origin of php packages

Distribution

Steps to Reproduce

0. Ensure the Systems and DNS plugins are installed

1. Click the DNS menu item under the Systems category (left hand of the screen)

2. Click Actions -> Create -> DNS Zone

3. Fill in zone name e.g. foo.

4. Fill in Primary DNS server e.g. dns.foo.

5. Fill in Mail address e.g. mail.foo.

6. Click OK

7. Click the Systems menu item under the Systems category

8. Click Actions -> Create -> Server

9. Fill in Name e.g. myHost

10. Enter an IP address e.g. 192.168.10.1

11. Click add

12. Click the DNS tab

13. Click Add DNS Settings

14. Select foo. from the zone list and click add

15. Click add under the DNS Records section

Note: If the fields in the modal dialogue are grey, cancel the dialogue box, save the host record, then edit it and go back to the DNS tab. This seems to be another intermittent bug.

16. Click Add to add an A record for 192.168.10.1
17. Click apply
18. Click the DNS menu item under the Systems category
19. Edit the zone you previously created
20. Change the name e.g. fooBar
21. Click apply

Expected behavior:

The DNS zone to be renamed, and for all hosts referencing that zone to have that reference updated.

Actual behavior:

Fatal error: Uncaught NonExistingLdapNodeException: Could not open dn zoneName=foo.,ou=dns,dc=nodomain in /usr/share/fusiondirectory/include/simpleplugin/class_simplePlugin.inc:232 
Stack trace: 
#0 /usr/share/fusiondirectory/plugins/admin/dns/class_dnsZone.inc(694): simplePlugin->__construct('zoneName=foo.,o...', NULL, Object(simpleTabs), true) 
#1 /usr/share/fusiondirectory/include/simpleplugin/class_simpleTabs.inc(88): dnsZone->__construct('zoneName=foo.,o...', NULL, Object(simpleTabs), true) 
#2 /usr/share/fusiondirectory/include/class_objects.inc(196): simpleTabs->__construct('dnsZone', 'zoneName=foo.,o...') 
#3 /usr/share/fusiondirectory/plugins/admin/systems/class_dnsHost.inc(461): objects::open('zoneName=foo.,o...', 'dnsZone') 
#4 /usr/share/fusiondirectory/plugins/admin/systems/class_dnsHost.inc(348): dnsHost::removeIpsFromZones(Array, Array) 
#5 /usr/share/fusiondirectory/include/simpleplugin/class_simpleTabs.inc(409): dnsHost->save() 
#6 /usr/share/fusiondirectory/plugins/admin/systems/tabs_server.inc(26): simpleTabs-> in /usr/share/fusiondirectory/include/simpleplugin/class_simplePlugin.inc on line 232

Reproduces how often: 50% it's weird and non-deterministic... But we're not running replication or anything fancy. I can also reproduce it on the fusiondirectory demo system that you host publically.