errors after turning off 2008r2 DCs

Question

so moving from our two 2008r2 DCs to 2012, moved FSMO roles successfully.
dcdiag and repadmin /shorepl ran successfully after that finished as well.

shut down the two 2008r2 servers for a time so we could make sure people could still sign on and such, and the few we tested worked.

turned the two 2008r2 servers back on, and suddenly I see errors in dcdiag and repmon that were not there before.
are these just errors that will clear after the servers have been up for a while?

here are some examples:

Default-First-Site-Name\old-ad via RPC
DSA object GUID:
Last attempt @ 2020-10-03 23:49:04 failed, result 1722 (0x6ba):
The RPC server is unavailable.
1 consecutive failure(s).
Last success @ 2020-10-03 23:03:01.

DC=DomainDnsZones,DC=mydomain,DC=com
Default-First-Site-Name\2008-ad via RPC
DSA object GUID: 501d77ca-e59f-4f6d-95a9-edf8ab32ebbb
Last attempt @ 2020-10-03 23:48:22 failed, result 1256 (0x4e8):
The remote system is not available. For information about network tr
oubleshooting, see Windows Help.
1 consecutive failure(s).
Last success @ 2020-10-03 22:47:40.

Starting test: SystemLog
An error event occurred. EventID: 0xC00038D6
Time Generated: 10/03/2020 23:57:08
Event String:
The DFS Namespace service could not initialize cross forest trust in
formation on this domain controller, but it will periodically retry the operatio
n. The return code is in the record data.
An error event occurred. EventID: 0x0000041F
Time Generated: 10/03/2020 23:57:20
Event String:
The processing of Group Policy failed. Windows could not resolve the
computer name. This could be caused by one of more of the following:
An error event occurred. EventID: 0xC00038D6
Time Generated: 10/03/2020 23:57:35
Event String:
The DFS Namespace service could not initialize cross forest trust in
formation on this domain controller, but it will periodically retry the operatio
n. The return code is in the record data.
An error event occurred. EventID: 0xC0002715
Time Generated: 10/03/2020 23:57:52
Event String:
DCOM got error "1068" attempting to start the service netprofm with
arguments "" in order to run the server:
An error event occurred. EventID: 0xC0001B6E
Time Generated: 10/03/2020 23:57:51
Event String:
The Network Location Awareness service hung on starting.
An error event occurred. EventID: 0xC0001B59
Time Generated: 10/03/2020 23:57:52
Event String:
The Network List Service service depends on the Network Location Awa
reness service which failed to start because of the following error:
An error event occurred. EventID: 0xC00038D6
Time Generated: 10/03/2020 23:58:05
Event String:

The DFS Namespace service could not initialize cross forest trust in
formation on this domain controller, but it will periodically retry the operatio
n. The return code is in the record data.
A warning event occurred. EventID: 0x00001695
Time Generated: 10/04/2020 00:15:54
Event String:
Dynamic registration or deletion of one or more DNS records associat
ed with DNS domain 'mydomain.com.' failed. These records are used by other compu
ters to locate this server as a domain controller (if the specified domain is an
Active Directory domain) or as an LDAP server (if the specified domain is an ap
plication partition).
An error event occurred. EventID: 0xC0002719

Answer 1

I'd check the event logs for more details on these errors.