I have a wierd one here.. I have a client running 2012 R2 - this runs their file & print sharing, Active Directory and backup software. The IT officer that I deal with has been asking me to help him with an issue, which is the server goes offline and has no connectivity. The server remains on and the OS is in tact but the network card says "no internet" unidentified network.
DHCP is running through the firewall which is 192.168.8.254 (Default Gateway / DHCP). Long story but we will leave that.. This firewall is around 8 years old btw so it could be the culprit and will be providing them with a test unit to see if we can narrow down but I haven't given you the curve ball yet.. wait for it.
Things we have tried;
- Checked error logs at the time it drops and nothing pops up at the time of the drop out.
- Testing all cables running from server, Tested OK.
- Tested connecting to the Firewall LAN port, tested OK.
- Swapped NICS from NIC4, to NIC3, NIC2 on the server and still no go.
- Checked all the IP config is ok. 192.168.8.11 (server) / 255.255.255.0 / 192.168.8.254 (gateway) / 127.0.0.1 (DNS)
- From a client's computer, provided a static IP address. Cannot connect to server or gateway so it does not see the network at all which is odd
- We have swapped out to a new switch as a test which we will leave there for the time being
- Checked DNS services, forwarders & entries are correct on the server
Yes the curve ball.. so my client has a MAC Book. It seems now that every time he connects his MAC book, the server connection comes alive, then the computers all come back online too.
We have tested over 4 times now and when he disconnects his MAC, the server goes offline within 10 mins, everytime! When he connects, the server comes online again.
When he connects to the network, he receives the 1st IP address given from DCHP (192.168.8.50). When he configures a static IP address from his MAC, he connect connect
I am waiting for the go ahead for me to drop the firewall in but are there any other suggestions or troubleshooting I should be looking at b/c I am stumpped.