Author Topic: No Internet, DNS not resolving  (Read 940 times)

vbn

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No Internet, DNS not resolving
« on: July 28, 2017, 06:44:56 pm »
I have just installed server, all modules have been activated basics as follows:
Zentyal 5, eth0 external DHCP, eth1 internal fixed, DNS transparent ticked, proxy also transparent. Eth0 is connected to cable modem with ISP specifics,  Eth1 is connected to router which is now just a switch. Other computers can access server, but have no internet access (browser blames DNS). You can, however, access internet through Administration interface.
I am almost ready to chuck it and try if I can get Nethserver to work for me.
VBN

vbn

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Re: No Internet, DNS not resolving
« Reply #1 on: July 28, 2017, 11:49:25 pm »
Should add, as you may already have deduced, that I am new to this and don't really know what I am doing.  I am coming from Microsoft Small Business Server 2011 which pretty much handled all this stuff automatically.  Also, one of the items connected to my router is my VOIP system, so every time I mess with this phone service is lost.
I anyone have any suggestions I would sure appreciate it.
Thanks

johnakki

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Re: No Internet, DNS not resolving
« Reply #2 on: August 15, 2017, 09:59:33 pm »
Can I assume that you've added some forwarders under DNS / Forwarders in the Zentyal admin console? If not, then that's your problem. Add 8.8.8.8 and 8.8.4.4 (Google DNS) for testing's sake, but ideally I would strongly recommend that you use OpenNIC servers: https://www.opennic.org/ (you'll see four IP addresses under the "find out more" button.
Assuming that your clients are Windows;
* open a command prompt on one of them, type the following and press enter. This tests DNS resolution against your client's default DNS server:
* nslookup bbc.co.uk
Now try again and explicitly provide the address of your Zentyal server to look up against
* nslookup bbc.co.uk [ip-address-of-zentyal]
* e.g. nslookup 192.168.1.1
Then try a a final time time with a public DNS server:
* nslookup bbc.co.uk 8.8.8.8

Post results back here

vbn

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Re: No Internet, DNS not resolving
« Reply #3 on: August 29, 2017, 12:27:46 am »
Sorry it took me so long to respond.  I had expected a notification from the forum when there was a reply.  Anyway in the meantime I have re-installed Zentyal and configured only one network interface.  I made that card external and connected it to my network router (similar configuration to Microsoft Small Business Server).  The DNS forwarders was changed to OpenNIC servers as you suggested.  Because of this single, external, NIC setup I can connect to the server only after creating or modifying Filtering rules from external networks to Zentyal.  So far I have allowed Webadmin and DNS and am trying to figure out which other ports to open without leaving me totally at risk from the outside.  With this configuration nslookup reports the addresses as it should.
I wish I could make it work with separate internal and external NICs.  In the meantime any suggestions on Firewall configuration for the current setup would be greatly appreciated.