I can't connect to school server from within school network

Question

At our school we have a server where we can access documents and similar. Accessing it is no problem if I connect to the network via VPN connection. But if I connect to the network via the WLAN of the school it can't find the domain.

I use a MacBook, so what I do is simply connecting to server via Finder (the address is correct, it works for anyone else). Then I get an error message suggesting that the server isn't available which isn't the case.

So I fired up Terminal and tried the following commands:

ping c206.hsr.ch

ping: cannot resolve c206.hsr.ch: Unknown host
------------------------------------------------
nslookup c206.hsr.ch

Server:     8.8.8.8
Address:    8.8.8.8#53

** server can't find c206.hsr.ch: NXDOMAIN
------------------------------------------------
host c206.hsr.ch

Host c206.hsr.ch not found: 3(NXDOMAIN)
------------------------------------------------
traceroute c206.hsr.ch

traceroute: unknown host c206.hsr.ch
------------------------------------------------
dig @8.8.8.8 c206.hsr.ch

; <<>> DiG 9.8.3-P1 <<>> @8.8.8.8 c206.hsr.ch
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 38513
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;c206.hsr.ch.           IN  A

;; AUTHORITY SECTION:
hsr.ch.         1498    IN  SOA ns1.hsr.ch. netzwerk.hsr.ch. 2014022602
14400 900 1209600 10800

;; Query time: 15 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Feb 26 16:03:26 2014
;; MSG SIZE  rcvd: 78

When using dig I get the same result if using a different DNS server like 4.2.2.2 (I use 8.8.8.8). I also tried creating a new account on my MacBook but that didn't work either.

Does anyone have any idea or some input? I'd be so thankful! Best regards!

Answer 1

Like Chris said, DNS 8.8.8.8 is google. DNS 4.2.2.2 is also a public DNS (Level 3 Comm.).
My provider also does not have a DNS entry for c206.hsr.ch, so we can assume your target host is on an internal school network only.

If internal only, then no public DNS will ever resolve the address for c206.hsr.ch. You mention in a comment that another classmate uses google-DNS successfully. I highly doubt that google is resolving that address for him. I believe he has another DNS entry in his configuration (one can often enter two DNS servers in a network configuration). You could try digging deeper into the network configurations of working PCs for more details. Look for multiple DNS server entries in working PCs.

Therefore I would conclude, in your VPN you are using another DNS, an internal one. I assume the PCs which work in the WLAN have a second DNS entry of the internal DNS server. MS Active Directory provides DNS; maybe your Windows-using classmates resolve the address with the help of Active Directory (?). Ask the IT support if an internal DNS server exists.

Please connect to the VPN and run the commands ping, nslookup, host and traceroute (like in the OP) and provide us with the output. You might see a working DNS entry...

Answer 2

You have probably 2 problems here:

• wrong DNS servers. Ask your IT Staff what DNS servers you should be using. 8.8.8.8 is google's DNS and while they are fine for "normal" browsing, they might not work with the internal stuff!

• this server might not be accessible from outside of specified IP ranges - it will be protected by firewall. Again, ask your IT Staff from which networks you can access this server.