• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 486
  • Last Modified:

Static IP vs. Dynamic IP

Hello all,

I have a Windows 2008 Core SP1 box that we use just to serve encryption keys to the network. Yesterday it fell off the network and we were not able to get it back on until we switched it from a static IP to a DHCP address. It was really strange, no matter what we did we could not get this server to communicate on the network unless it has a DHCP address. Once we put the DCHP address on the box, we can see the server and all network resources and the whole network can see the server.

One other thing, I disconnected the server from the network hooked up a 5 port router and 2 other laptops and assigned static IPs to all, and everything could see everything.  This told me that it was not an issue with the network card, since it worked when off the domain network. Our network is AD 2008 R2 SP1 with 3 DC's and those are also the DNS Servers on the domain.

Now my boss wants to know why this particular server fell off the network, and he isn't accepting my I don't know answer. Will someone please help me figure out why this happened?

Thanks in advance.
0
EKRIN
Asked:
EKRIN
2 Solutions
 
Joseph MoodyBlogger and wearer of all hats.Commented:
It sounds like a DNS issue. Were you able to ping  the server by IP yesterday?
0
 
EKRINAuthor Commented:
That is what we were thinking, and no, the Core Server could not ping anything except itself, and nothing else could ping the core server.
0
 
Joseph MoodyBlogger and wearer of all hats.Commented:
by hostname and IP?
0
The IT Degree for Career Advancement

Earn your B.S. in Network Operations and Security and become a network and IT security expert. This WGU degree program curriculum was designed with tech-savvy, self-motivated students in mind – allowing you to use your technical expertise, to address real-world business problems.

 
EKRINAuthor Commented:
correct, both ways by hostname and IP
0
 
Joseph MoodyBlogger and wearer of all hats.Commented:
That isn't a dns problem then. Even if dns is disable, you should have still been able to ping by IP.

Check the event log (system) for any network/dhcp/dns errors. I have seen this problem with printer NICs but never with a server.

If it happens again, I would replace the NIC.
0
 
EKRINAuthor Commented:
Here is one more thing...in the past 2 or 3 weeks we have had about 4 computers drop off the domain. Basically the same issue. We had to remove them from the domain and then add them back for them to see resources and for the network to see them.
0
 
Joseph MoodyBlogger and wearer of all hats.Commented:
Thank you for the information. Knowing that, I would look at routing/switching configs and errors.
0
 
rindiCommented:
Are you sure the static IP you gave the server isn't also served by your DHCP server? If the DHCP server has given out a lease of the same IP you have set as static IP on the server, you would have these type of issues...

Normally in my point of view the best way to assign static IP's is not to edit the properties on the PC with the NIC itself, but rather to use the DHCP server and make it assign the static IP to the particular MAC address of the NIC on your PC. That way you don't ruin into conflicts, and everything is centrally managed, (that way it isn't possible for the same IP to be assigned to 2 different NIC's).
0
 
EKRINAuthor Commented:
Here are some of the errors in Event viewer:
The system failed to register host (A or AAAA) resource records for  network adapter
with settings:

   Adapter Name : {8D86125F-8BD2-40C0-ABC2-F95F519E7D1D}
   Host Name : KEYMASTER
   Primary Domain Suffix : domain.local
   DNS server list :
           10.10.40.10, 10.10.40.11, 10.10.40.16
   Sent update to server : <?>
   IP Address(es) :
     10.10.40.24

 Either the DNS server does not support the DNS dynamic update protocol  or the authoritative zone for the specified DNS domain name does not  accept dynamic updates.

 To register the DNS host (A or AAAA) resource records using the specific DNS domain name and IP addresses for this adapter, contact your DNS  server or network systems administrator.

AND

This computer was not able to set up a secure session with a domain controller in domain domain due to the following:
There are currently no logon servers available to service the logon request.
This may lead to authentication problems. Make sure that this computer is connected to the network. If the problem persists, please contact your domain administrator.  

ADDITIONAL INFO
If this computer is a domain controller for the specified domain, it sets up the secure session to the primary domain controller emulator in the specified domain. Otherwise, this computer sets up the secure session to any domain controller in the specified domain.
0
 
EKRINAuthor Commented:
Hi rindi,

I am sure that IP is not reserved and was not had not be assigned to anything else. Even now if I change the IP of keymaster to static it still locks it out of the network and has no access to servers or servers have no access to it.

Thanks,
0
 
EKRINAuthor Commented:
One more error under security that is repeated:

Windows Firewall was unable to notify the user that it blocked an application from accepting incoming connections on the network.

Error Code:      2
0
 
Joseph MoodyBlogger and wearer of all hats.Commented:
Is 10.10.40.24 the static or DHCP address?
0
 
EKRINAuthor Commented:
The machine has 2 nics and one is 10.10.40.24 and the other is 10.10.40.21. I tried disabling one and using the other, using both and nothing worked until I made them dhcp
0
 
qf3l3kCommented:
Usually similar situation happens when you have IP conflict in network.
You can disconnect server from network (with static IP when it's not working) and still try to ping same IP server should have.
That will give you answer if there is IP conflict in the network or not.

Also, one more question, on that server as you have 2 NICs with IP addresses from same subnet assigned to both of them, do you have default gateway defined on both adapters as well?

Are computers on the same subnet as server or server is separated into different IP range?
0
 
EKRINAuthor Commented:
Solution was ip address conflict. From the phone server dhcp server. DOH.
0

Featured Post

Microsoft Certification Exam 74-409

Veeam® is happy to provide the Microsoft community with a study guide prepared by MVP and MCT, Orin Thomas. This guide will take you through each of the exam objectives, helping you to prepare for and pass the examination.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now