Cannot Connect to Domain Controller 2012 R2

Cannot Connect to Domain Controller 2012 R2

The server appears to have all of the correct set-up (it is a Global Catalogue) and I have seized the roles from the other GCs so that it has all of the FSMO roles onboard. I have removed all of the old server records (I am trying to bring up just this DC without the rest of the network for recovering something) and I still cannot see that the Active Directory is properly running.

I am seeing the following:

Log Name:      System
Source:        Microsoft-Windows-GroupPolicy
Date:          03/10/2019 16:00:57
Event ID:      1129
Task Category: None
Level:         Error
Keywords:      
User:          DOMAIN\sys_admin
Computer:      server.DOMAIN.local
Description:
The processing of Group Policy failed because of lack of network connectivity to a domain controller. This may be a transient condition. A success message would be generated once the machine gets connected to the domain controller and Group Policy has successfully processed. If you do not see a success message for several hours, then contact your administrator.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Microsoft-Windows-GroupPolicy" Guid="{AEA1B4FA-97D1-45F2-A64C-4D69FFFD92C9}" />
    <EventID>1129</EventID>
    <Version>0</Version>
    <Level>2</Level>
    <Task>0</Task>
    <Opcode>0</Opcode>
    <Keywords>0x8000000000000000</Keywords>
    <TimeCreated SystemTime="2019-10-03T15:00:57.503758300Z" />
    <EventRecordID>284572</EventRecordID>
    <Correlation ActivityID="{16136B91-2088-483C-A4EF-6199D2C013AF}" />
    <Execution ProcessID="960" ThreadID="3672" />
    <Channel>System</Channel>
    <Computer>server.DOMAIN.local</Computer>
    <Security UserID="S-1-5-21-3422917438-1280912437-4267239440-500" />
  </System>
  <EventData>
    <Data Name="SupportInfo1">1</Data>
    <Data Name="SupportInfo2">1967</Data>
    <Data Name="ProcessingMode">1</Data>
    <Data Name="ProcessingTimeInMilliseconds">15</Data>
    <Data Name="ErrorCode">1222</Data>
    <Data Name="ErrorDescription">The network is not present or not started. </Data>
  </EventData>
</Event>


This is what I see when I try and start AD users and computers:



Naming information cannot be located for the following reason:
The server is not operational.

Also seeing:

Log Name:      Directory Service
Source:        Microsoft-Windows-ActiveDirectory_DomainService
Date:          03/10/2019 16:56:16
Event ID:      1311
Task Category: Knowledge Consistency Checker
Level:         Error
Keywords:      Classic
User:          ANONYMOUS LOGON
Computer:      SERVER.DOMAIN.local
Description:
The Knowledge Consistency Checker (KCC) has detected problems with the following directory partition.

Directory partition:
DC=DomainDnsZones,DC=DOMAIN,DC=local

There is insufficient site connectivity information for the KCC to create a spanning tree replication topology. Or, one or more directory servers with this directory partition are unable to replicate the directory partition information. This is probably due to inaccessible directory servers.

User Action
Perform one of the following actions:
- Publish sufficient site connectivity information so that the KCC can determine a route by which this directory partition can reach this site. This is the preferred option.
- Add a Connection object to a directory service that contains the directory partition in this site from a directory service that contains the same directory partition in another site.

If neither of the tasks correct this condition, see previous events logged by the KCC that identify the inaccessible directory servers.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Microsoft-Windows-ActiveDirectory_DomainService" Guid="{GUID}" EventSourceName="NTDS General" />
    <EventID Qualifiers="49152">1311</EventID>
    <Version>0</Version>
    <Level>2</Level>
    <Task>1</Task>
    <Opcode>0</Opcode>
    <Keywords>0x8080000000000000</Keywords>
    <TimeCreated SystemTime="2019-10-03T15:56:16.254739200Z" />
    <EventRecordID>296888</EventRecordID>
    <Correlation />
    <Execution ProcessID="560" ThreadID="1236" />
    <Channel>Directory Service</Channel>
    <Computer>SERVER.DOMAIN.local</Computer>
    <Security UserID="S-1-5-7" />
  </System>
  <EventData>
    <Data>DC=DomainDnsZones,DC=DOMAIN,DC=local</Data>
  </EventData>
</Event>

Is it the connectivity I must restore - can I botch it just to use it's own database for AD?