Question Help with DNS Server

naviseyer

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Nov 8, 2016
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I know this is something to do with my DNS server I just cant figure out whats going on.
I am running windows server 2012 r2 . Its configured as a host with 2 virtual machines.
1 virtual machines acts as our DNS and also holds all our data in shared folders the 2nd virtual machine is only for quickbooks.
Everything was good last night . The backup completed at 9pm. So i know everything was good until atleast 9pm.
I know its not my internet connection because my wireless router is able to grab access to the net .

When i pull up networks The DNS server and virtual machines do not show up. When i scan the network the Nics for the server dont show up.
i have reset Both virtual machines , I have done a restart of the server as a whole.
From a workstation when i go to N.I.C settings
its showing ethernet connection to network 2 instead of my actual domain name which would be normal/
the ip address assigned to this workstation using DHCP is 192.168.1.149..the default gateway is correct
the dhcp server ip address is correct, the Dns server ip address again is correct.

I have checked the event logs and found nothing between yesterday and today.

we use VOIP phones they are all working correctly ,

when i ping the DNS server i get request timed out.
I have reset all nics on server. i am not sure what happened When it happened or why it happened. All the settings are the same and nothing appears incorrect.

Anyone have any thoughts....

Thanks

Ivan
 
Have you tried accessing the servers via other types of access (SMB maybe) or are you just trying ICMP? Sometimes things like updates can reset Windows firewall settings to disallow connections like ICMP.
This could also be incorrect settings on the virtual switch. Can the quickbooks server and DNS server (the 2 VMs) see each other?
 

naviseyer

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Nov 8, 2016
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When i am on the actual server and go to hyper V manager i can access and connect to both AMDCO1 which is the DNS server and the Data . I can also access and connect to AMQB01 which is the quickbooks server. The reason i am so confused is all the settings are correct. I dont do auto updates and normally manual update once a month . So i dont know what changed , why it changed or when it changed. All the setting are the same and correct setting that were working just fine yesterday.
Today it just seems like its not finding the Domain , It keep jumping on as unidentified network .
 

naviseyer

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Nov 8, 2016
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I have never seen anything like this. Everything seems correct . No updates no changes all settings correct but the Server can’t see the network and now workstations are seeing the server . I don’t get it . I have checked from server and from workstation both have everything set up correctly but for whatever reason the workstations are not seeing the DNS .
I’m gonna call it a day and start fresh tomorrow I’m going to bet it’s something very simple that I’m missing but I’m getting frustrated... gonna step back for the night... still open to any ideas ..thanks again
 

naviseyer

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Nov 8, 2016
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Good afternoon everyone... Well I am back at it today and i was 100 percent correct. Something small and silly i overlooked. For those that dont really care it was a issue with a switch... I will give a more detailed answer for those that would like to know for learning purposes.

Over a year ago i upgraded our switches. For some reason which i have never been able to figure out after upgrading our switches every couple of weeks they would just lock up on me. Once they locked up the network would bypass the default gateway and start getting their ip addresses from either the firewall or the router itself . usually grabbing a 169..... . So i ended up going back to the old switches because i was never able to recreate the issue and it was so random i never solved it,
Im sure i must have posted something about it on here .

Anyway that was the same issue i ran into yesterday but didnt even think about the switches. It has been so long since i had this happen . I also cant recall it ever happening with the switches we are currently using . Only with the ones after the upgrade which are just sitting in a supply closet .

OK well if anyone here has had this happen . Please let me know if you were able to recreate the problem or if you found a permanent solution. Again this was a every couple of weeks issue after upgrading the switches. Once i went back to the older switches the problem stopped and i cant recall if i had this issue with the current switches prior to
yesterday.

Thanks everyone ...
i guess people can work tomorrow if we dont get to much snow here in NYC.
 
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