game_over Posted April 7, 2015 Share Posted April 7, 2015 I split my network into multiple VLANs putting all the servers into a VLAN and clients on to a separate VLAN. I have changed the server IPs to reflect this. My main DC is 2008 which I am slowly migrating to a new 2012 r2 server, which is currently the secondary DC. Everything seems OK except from the Group Policy Management Console on the 2012, when loading it says: "The specified domain controller cannot be contacted" I can select the Master manually but then I get a different error: "The RPC Server was unavailable" Most google results relate to firewall issues, however the Windows Firewall is disabled on both servers. 2012 server is a VM. .. I have also noticed I can't access it remotely, I need to go through Hyper V Manager on the host. Any ideas? Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/ Share on other sites More sharing options...
+BudMan MVC Posted April 7, 2015 MVC Share Posted April 7, 2015 And what do you have in your AD.. Why did you split them to different vlans? And your not firewalling between the segments? What is doing the routing between your segments? Can you give us details of what is routing and what your segments are? Do you have dns on both servers? What does dcdiag say ? https://technet.microsoft.com/en-us/library/cc731968.aspx Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809474 Share on other sites More sharing options...
binaryzero Posted April 7, 2015 Share Posted April 7, 2015 Sure you're not confusing VLANs with IPAM\different subnets (different IP ranges for servers\clients)? Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809488 Share on other sites More sharing options...
+BudMan MVC Posted April 7, 2015 MVC Share Posted April 7, 2015 ^ Exactly -- think maybe they just changed the address space and running both over the same physical network. Or did they just say lets use 192.168.0.1-254 for clients and 192.168.1.1-254 for servers in our 192.168.0.0/23 ?? Details will help us help you. Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809490 Share on other sites More sharing options...
game_over Posted April 7, 2015 Author Share Posted April 7, 2015 On 07/04/2015 at 10:43, BudMan said: And what do you have in your AD.. Why did you split them to different vlans? And your not firewalling between the segments? What is doing the routing between your segments? Can you give us details of what is routing and what your segments are? Do you have dns on both servers? What does dcdiag say ? https://technet.microsoft.com/en-us/library/cc731968.aspx Because we are coming away from our local authority network and had it reconfigured as a result.. we now have multiple VLANs: servers, printers, wireless APs, finance, workstations. Firewall was just disabled for testing. VLAN NAME, IP, ADDRESS RANGE, ROUTER, DEFAULT GATEWAY VLAN 80 ROUTING NETWORK 10.83.125.208 /28 10.83.125.209 10.83.125.215 VLAN 81 VLAN 82 FINANCE 10.83.121.0 /24 10.83.121.1 VLAN 83 PRINTERS 10.83.122.0 /24 10.83.122.1 VLAN 84 SERVERS 10.83.123.0 /24 10.83.123.1 VLAN 85 WIRELESS AP 10.83.124.0 /24 10.83.124.1 VLAN 86 WORKSTATIONS 10.83.112.0 /24 10.83.112.1 Yes DNS is on both servers. Starting test: FrsEvent There are warning or error events within the last 24 hours after the SYSVOL has been shared. Failing SYSVOL replication problems may cause Group Policy problems. Starting test: NetLogons [WVPS-SCH-SRV] User credentials does not have permission to perform this operation. The account used for this test must have network logon privileges for this machine's domain. ......................... WVPS-SCH-SRV failed test NetLogons Starting test: Replications [Replications Check,WVPS-SCH-SRV] DsReplicaGetInfo(PENDING_OPS, NULL) failed, error 0x2105 "Replication access was denied." ......................... WVPS-SCH-SRV failed test Replications Starting test: Services Could not open NTDS Service on WVPS-SCH-SRV, error 0x5 "Access is denied." ......................... WVPS-SCH-SRV failed test Services Seems like some permission errors? Maybe unrelated to the networking changes? It is strange this only happened after network changes, these errors weren't present previously. Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809522 Share on other sites More sharing options...
+BudMan MVC Posted April 7, 2015 MVC Share Posted April 7, 2015 Well you might be getting access denied because of dns problems pointing to old IPs, etc.. Validate dns with dcdiag.. As to firewalls - not talking software firewall.. What is actually routing between your segments? A layer 3 switch? Router/Firewall distro, hardware router? Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809534 Share on other sites More sharing options...
binaryzero Posted April 7, 2015 Share Posted April 7, 2015 Can you access other VMs on your Hyper-V host remotely? Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809552 Share on other sites More sharing options...
sc302 Veteran Posted April 7, 2015 Veteran Share Posted April 7, 2015 As budman stated you are probably missing something, a dns entry on your network adapters possibly. may need to run a ipconfig /registerdns to force an immediate update to dns. If you have internet access, I would be more than happy to look at this for you. open up a teamviewer session (go to teamviewer.com) and pm me the id and password. tehsteve86 1 Share Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596809588 Share on other sites More sharing options...
game_over Posted April 7, 2015 Author Share Posted April 7, 2015 On 07/04/2015 at 12:24, BudMan said: Well you might be getting access denied because of dns problems pointing to old IPs, etc.. Validate dns with dcdiag.. As to firewalls - not talking software firewall.. What is actually routing between your segments? A layer 3 switch? Router/Firewall distro, hardware router? Cisco Catalyst 3560 v2 On 07/04/2015 at 12:38, Jared- said: Can you access other VMs on your Hyper-V host remotely? Yes they seem ok.. We have 3 VMs on the server, one of them is the domain controller which is the only one I am having trouble from. On 07/04/2015 at 13:05, sc302 said: As budman stated you are probably missing something, a dns entry on your network adapters possibly. may need to run a ipconfig /registerdns to force an immediate update to dns. If you have internet access, I would be more than happy to look at this for you. open up a teamviewer session (go to teamviewer.com) and pm me the id and password. I am off site now but will give it a go tomorrow.. If I need help I will send you team view details in PM, thanks for the offer. Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596810062 Share on other sites More sharing options...
game_over Posted April 8, 2015 Author Share Posted April 8, 2015 ipconfig /registerdns seems to have brought everything back. Thanks Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596810562 Share on other sites More sharing options...
sc302 Veteran Posted April 8, 2015 Veteran Share Posted April 8, 2015 Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596810810 Share on other sites More sharing options...
binaryzero Posted April 9, 2015 Share Posted April 9, 2015 LOL DNS the entire time. Link to comment https://www.neowin.net/forum/topic/1252694-changed-server-ips-getting-errors/#findComment-596811674 Share on other sites More sharing options...
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