Destination net unreachable when pinging

[Joel amos]

Whenever I ping my university's website, emu.edu, I get the message: "Destination net unreachable." This only happens for all subdirectories and subdomains of emu.edu. I am able to visit the main website via my web browser, but problems arise when I try to connect to vpn.emu.edu via Cisco AnyConnect Secure Mobility Client, which allows me to connect to my school's network.

Three days ago, my school added a second ISP to double the school's bandwidth. Could this be in any way related? Because four days ago, I was able to connect to the VPN. The result from Isitdownrightnow would suggest that the problem is my own. But then, how does one explain being able to connect well to other sites?

 

[DelJo63]

Whenever I ping my university's website, emu.edu, I get the message: "Destination net unreachable."

The message means what it says - - there is no path to the address given to ping. You can see for yourself with this test:

get a command prompt and enter

• first find your pc address on the lan with IPCONFIG
• (mine shows up as: IPv4 Address. . . : 192.168.0.5)
• now PING the device at x.x.x.253
• in my case PING 192.168.0.253

you get

ping 192.168.0.253
Pinging 192.168.0.253 with 32 bytes of data:
Reply from 192.168.0.5: Destination host unreachable.
Reply from 192.168.0.5: Destination host unreachable.

Let's say you're trying to ping the system webserver.emu.edu but it is behind a firewall. The firewall allows port 80 so browsing works.
The path for ping looks like

• yourPC - - EMU.firewall -- webserver

Ping gets to the firewall, but does not move thru it and thus you get your Dest Not Reachable.

Why? Because PING is not port related (like port 80 ->webservers) but rather is a protocol.

 

[Joel amos]

I'm a little confused; how is emu.edu different than any other website?

 

[DelJo63]

It is not, but fail to understand that PING is not required to respond for any website. If it does, nice, but the test is using the browser itself

 

[Joel amos]

Well, I have tested vpn.emu.edu is the browser, and I am not able to connect. I thought the error message that I am getting when pinging would be related.

 

[DelJo63]

VPN - - By that name, I would never expect ping to respond, as that (I would assume) would be the VPN server and it would respond on a secured port.

Have you ever been able to access the VPN or the website (usually they are public and not on a vpn server).

 

[Joel amos]

Yes, as per my post, I was able to just four days ago.

 

[DelJo63]

Whois emu.edu

Domain Name: EMU.EDU

Registrant:
  Eastern Mennonite University
  1200 Park Road
  Harrisonburg, VA 22801-2462
  UNITED STATES

Name Servers:
  INSERV1.EMU.EDU  199.111.20.10
  INSERV2.EMU.EDU  199.111.20.12

nslookup emu.edu

$ nslookup emu.edu
Non-authoritative answer:
Server:  dns-cac-lb-01.rr.com
Address:  209.18.47.61

Name:  emu.edu
Address:  199.111.20.20

nslookup vpn.emu.edu

Non-authoritative answer:
Server:  dns-cac-lb-01.rr.com
Address:  209.18.47.61

Name:  vpn.emu.edu
Address:  199.111.20.110

ping either {vpn.}emu.edu
>> TIMEOUT

Tracert emu.edu

Tracing route to emu.edu [199.111.20.20]
over a maximum of 30 hops:

  1  <1 ms  <1 ms  <1 ms  localrouter [192.168.0.1]
  2  10 ms  8 ms  8 ms  cpe-75-85-0-1.socal.res.rr.com [75.85.0.1]
  3  9 ms  11 ms  9 ms  tge0-9-0-23.wlvgcabn02h.socal.rr.com [24.30.172.141]
  4  13 ms  11 ms  15 ms  agg22.vnnycajz02r.socal.rr.com [72.129.14.168]
  5  14 ms  10 ms  15 ms  agg29.tustcaft01r.socal.rr.com [72.129.13.2]
  6  14 ms  14 ms  23 ms  bu-ether16.tustca4200w-bcr00.tbone.rr.com [66.109.6.64]
  7  11 ms  11 ms  12 ms  0.ae2.pr1.lax10.tbone.rr.com [107.14.19.54]
  8  13 ms  15 ms  14 ms  las-b21-link.telia.net [62.115.36.57]
  9  52 ms  50 ms  49 ms  dls-b21-link.telia.net [80.91.254.170]
 10  70 ms  79 ms  69 ms  atl-bb1-link.telia.net [80.91.254.164]
 11  68 ms  69 ms  69 ms  shentel-ic-307320-atl-bb1.c.telia.net [80.239.194.106]
 12  *  *  *  Request timed out.
 13  90 ms  91 ms  89 ms  204.111.0.190 <<<<
 14  *  *  *  Request timed out.
 15  *  *  *  Request timed out.
 16  *  *  *  Request timed out.
 17  *  *  *  Request timed out.

204.111.0.190 =>

OrgName: Shentel Service Company
OrgId: SHENTE
Address: 124 South Main Street
City: Edinburg
StateProv: VA​

looks like an ISP

 

[Joel amos]

So does this indicate that it is not a problem with my connection?

 

[DelJo63]

Yes - - at least from Los Angeles, the path to emu.edu is broken.

you can test for yourself, from your location, by getting a command prompt and entering

tracert emu.edu​

the last response should be the ip-address thereof, aka 199.111.20.20

 

[Joel amos]

Yes, it is broken. Why am I able to connect to the site via a web browser?

Also, Shentel is the new ISP that the school just added.

 

[DelJo63]

Investigating DNS:::

$ nslookup emu.edu 8.8.8.8
Non-authoritative answer:
Server:  google-public-dns-a.google.com
Address:  8.8.8.8
Name:  emu.edu
Address:  199.111.20.20

$ nslookup www.emu.edu 8.8.8.8
Non-authoritative answer:
Server:  google-public-dns-a.google.com
Address:  8.8.8.8
Name:  www.emu.edu
Address:  199.111.20.20

$ nslookup vpn.emu.edu 8.8.8.8
Non-authoritative answer:
Server:  google-public-dns-a.google.com
Address:  8.8.8.8
Name:  vpn.emu.edu
Address:  199.111.20.110

So the first two urls map to the same server while the vpn is isolated.

I too can reach www.emu.edu with my browser and yet tracert says the path is broken (btw tracert uses ping to perform its function).
IMO, this demonstrates a comment earlier that a website is not required to respond to ping.

1. in all cases, regardless of the target being tested, ping fails for {,vpn,www}.emu.edu
2. yet http (port 80) can access the website

Your issue lay between the new ISP and the VPN server. I would guess the ISP has not setup the firewall for the vpn traffic.

 

[Joel amos]

Thanks for the help!