Edited now that I understand more the issue:
My Windows 2008R2 server is having a strange networking problem. I can access the server via RDP, File Sharing, etc.
But from the server, I can't connect to anything on the network - I can't connect to the email server, web servers, nothing!
I could not find anything in the event log that is related.
As I have 200+ users using the file share from it, I don't want to restart it until way late at night when nobody is using it.
So I'm wondering if anybody knows what I should look for, anything I can do, etc, to remedy this without restarting.
Also, what could be the cause - I obviously don't know that restarting it will resolve anything.
Earlier post for info
A Windows 2008R2 server is having issues accessing domain resources. For example when logged on to this server, if I try:
\server1\ I get Error code 0x80004005 - Unspecified Error
gpupdate fails with "The processing of Group Policy failed. Windows could not resolve the user name. This could be caused by one of more of the following: a) Name Resolution failure on the current domain controller. b) Active Directory Replication Latency..."
Name resolution works using nslookup but seem to fail when going through a Windows application.
For example, telnet into my email server fails from this server but works from other computers.
It's not a problem with the network access list blocking access. Even accessing resources on the same VLAN does not work.
It's not only name resolution because accessing the servers by IP Address also does not work.
And it's not a general connectivity issue either since I'm accessing the server via RDP and I can use remote administration tools.
I can even access the windows shares on this server from my computer.
But from this computer, I can't access other servers. It also fails in querying Active Directory to validate some authentication requests.
EDIT: An interesting thing is that if I do:
telnet emailserver 25 I get connect failed.
And I also get the same if I do telnet 10.5.2.1 25
But I can ping it. It's not an issue with the email server as I can telnet into it from another server in the same subnet.
It's not a general broad networking issue either since the windows shares on this server are being accessed by many users right now and I'm currently accessing it via RDP as stated earlier.
Accessing a samba share of a Linux server by IP Address also does not work. Seems like this may not be related to the domain controller.
Accessing the servier's own shares does not work either when done from the server itself.
Restarting the server handled the issue without doing anything else. Does not tell me what happened however. If anybody has an idea of what could have created this situation, let me know. Otherwise, rebooting is the solution to this until someone finds a better one.