Not sure if this is safe to delete. I have read that these AD domain name records are created by netlogon service, and/or others, and not changeable. I have two domain controllers, each showing correctly in AD DNS, but there's a third record with an IP of 192.168.203.0 ??? I don't know where that came from. Is it safe to delete?
I ask because this seems to be causing some issues with Exchange Autodiscover internally. dcdiag (with no args) returns all ok, and there's no errors in Event Logs regarding replication or AD. If I run dcdiag with /test:dns I get all kinds of errors with all the hosts on the network tested as DC's.
Just a little background. We are currently in the process of migrating from 2003 to 2010 Exchange server and have setup a new 2012 R2 DC. The old DC is 03 with Exchange. (I know, not good, but was setup 10 years ago by someone else!). I have a lab setup with the same servers (from images taken before migration) and there's no IP with .0 in the root of the domain there. So this showed up on the production systems since upgrades started recently. The 03 server will be decommissioned in the next week or so, so maybe it will go away in that process?
I appreciate any advice. Thank you!
Here's an nslookup on the domain for reference, you can see the .0 record.
C:\>nslookup Default Server: UnKnown Address: fdcc:12e5:12e5:cb::2 > server 192.168.203.222 Default Server: bert.yourdomain.org Address: 192.168.203.222 > set type=any > yourdomain.org Server: bert.yourdomain.org Address: 192.168.203.222 yourdomain.org internet address = 192.168.203.4 yourdomain.org internet address = 192.168.203.0 yourdomain.org internet address = 192.168.203.222 yourdomain.org nameserver = mail.yourdomain.org yourdomain.org nameserver = bert.yourdomain.org yourdomain.org primary name server = bert.yourdomain.org responsible mail addr = hostmaster.yourdomain.org serial = 15137 refresh = 900 (15 mins) retry = 600 (10 mins) expire = 86400 (1 day) default TTL = 3600 (1 hour) yourdomain.org text = "v=spf1 ip4:192.168.203.4 ~all" yourdomain.org AAAA IPv6 address = fdcc:12e5:12e5:cb:3c2e:de4c:9d70:25b5 yourdomain.org AAAA IPv6 address = fdcc:12e5:12e5:cb::2 mail.yourdomain.org internet address = 192.168.203.4 bert.yourdomain.org internet address = 192.168.203.222 bert.yourdomain.org AAAA IPv6 address = fdcc:12e5:12e5:cb:3c2e:de4c:9d70:25b5 bert.yourdomain.org AAAA IPv6 address = fdcc:12e5:12e5:cb::2 >
I can provide the standard dcdiag output if you would like, but here's the /test:dns output, just a snippet (its long). All tests pass on a standard dcdiag. But with test:dns, it runs through all IP's on the network, and doesn't even show a test for the actual DC's, and of course they all fail.
C:\Windows\system32>dcdiag /test:dns Directory Server Diagnosis Performing initial setup: Trying to find home server... Home Server = BERT * Identified AD Forest. Done gathering initial info. Doing initial required tests Testing server: Default-First-Site-Name\BERT Starting test: Connectivity ......................... BERT passed test Connectivity Doing primary tests Testing server: Default-First-Site-Name\BERT Starting test: DNS DNS Tests are running and not hung. Please wait a few minutes... ......................... BERT passed test DNS Running partition tests on : ForestDnsZones Running partition tests on : DomainDnsZones Running partition tests on : Schema Running partition tests on : Configuration Running partition tests on : yourdomain Running enterprise tests on : yourdomain.org Starting test: DNS Summary of test results for DNS servers used by the above domain controllers: DNS server: 192.168.203.100 (yourdomain.org.) 1 test failure on this DNS server DNS server: 192.168.203.101 (yourdomain.org.) 1 test failure on this DNS server DNS server: 192.168.203.103 (yourdomain.org.) 1 test failure on this DNS server DNS server: 192.168.203.16 (yourdomain.org.) 1 test failure on this DNS server PTR record query for the 220.127.116.11.in-addr.arpa. failed on the DNS server 192.168.203.16 DNS server: 192.168.203.19 (yourdomain.org.) 1 test failure on this DNS server PTR record query for the 18.104.22.168.in-addr.arpa. failed on the DNS server 192.168.203.19 DNS server: 192.168.203.20 (yourdomain.org.) 1 test failure on this DNS server