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bassjunky's profile

New Member

 • 

5 Messages

Friday, August 19th, 2022 8:33 PM

Unable to VPN

For the last week or so, I have not been able to connect to my work's VPN or connect to a FTP server that I use weekly.  I have tried multiple computers in the house (Mac and PC) with the same results, and confirmed that it is not an issue with my work.  What's strange is if I use the hotspot on my phone, I have no issues.  It's almost like ATT is blocking access to these particular IP addresses.  Any thoughts?  Thanks.

Accepted Solution

ACE - Expert

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35.8K Messages

2 years ago

While it is possible AT&T is blocking traffic to these addresses, it has been my experience that it is more likely that the servers at the other end have identified your IP address as belong to a range of undesirable users and is blocking it.

Yes, yes, I know they say they aren't.  They always say that.

Let's try to troubleshoot this and see if we can identify where the problem is.  If the problem is within AT&T's network, we can try to get them involved (though it will not be easy).  If it appears to get through AT&T's network okay, then we have more evidence for you to use with speaking with the owner of the VPN/FTP servers.

Start by doing a traceroute to the IP addresses of the VPN and FTP servers.  Post your results here.

UPDATE: I did think of two things that might be causing this that might be worth eliminating:

1) Sometimes an issue like this is with IPv6 not working quite right... if you have IPv6 on, you might want to disable it in the Gateway and see if that fixes the problem.

2) I am also assuming that you haven't enabled AT&T Internet Security.  If you have, you should try disabling that to see if that solves your issue as well.

(edited)

New Member

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5 Messages

2 years ago

Thank you!  Yes, it appears to be possibly on my work's end.  I did disable Internet Security and IPv6, even those had always been enabled when it worked.  Still no dice.  The tracert for the VPN and FTP both look the same.

Tracing route to 142.147.51.39 over a maximum of 30 hops

  1     1 ms     1 ms     1 ms  dsldevice.attlocal.net [192.168.1.254]
  2     4 ms     2 ms     2 ms  162-236-176-1.lightspeed.rcsntx.sbcglobal.net [162.236.176.1]
  3     5 ms     6 ms     5 ms  71.155.13.178
  4     *        *        *     Request timed out.
  5    12 ms    13 ms    15 ms  32.130.16.9
  6     6 ms     9 ms     5 ms  dlstx409me9.ip.att.net [12.122.100.105]
  7     7 ms     9 ms   118 ms  12.126.193.30
  8     *        *        *     Request timed out.
  9     *        *        *     Request timed out.
 10     *        *        *     Request timed out.
 11     *        *        *     Request timed out.
 12     *        *        *     Request timed out.
 13     *        *        *     Request timed out.
 14     *        *        *     Request timed out.
 15     *        *        *     Request timed out.
 16     *        *        *     Request timed out.
 17     *        *        *     Request timed out.
 18     *        *        *     Request timed out.
 19     *        *        *     Request timed out.
 20     *        *        *     Request timed out.
 21     *        *        *     Request timed out.
 22     *        *        *     Request timed out.
 23     *        *        *     Request timed out.
 24     *        *        *     Request timed out.
 25     *        *        *     Request timed out.
 26     *        *        *     Request timed out.
 27     *        *        *     Request timed out.
 28     *        *        *     Request timed out.
 29     *        *        *     Request timed out.
 30     *        *        *     Request timed out.

Trace complete.

Thanks again for your help.

(edited)

ACE - Expert

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35.8K Messages

2 years ago

My traceroute to the destination ends the same as yours, i.e. the last hop to respond is 12.126.193.30.

Can you do a traceroute using the phone hotspot for comparison?  We need to see how (or if) the traceroutes differ. 

ACE - Guru

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9.9K Messages

2 years ago

Another data point that may or may not be useful but from the West Coast I get this....

  8    52 ms    47 ms    47 ms  cr2.dvmco.ip.att.net [12.122.31.22]
  9    46 ms    46 ms    46 ms  dlstx22crs.ip.att.net [12.122.2.85]
 10    52 ms    58 ms    52 ms  dlstx21crs.ip.att.net [12.122.1.209]
 11    46 ms    47 ms    46 ms  dlstx409me9.ip.att.net [12.122.100.105]
 12    49 ms    49 ms    49 ms  12.126.193.30
 13     *        *        *     Request timed out.
 14     *        *        *     Request timed out.
 15     *        *        *     Request timed out.
 16     *        *        *     Request timed out.
 17    50 ms    50 ms    50 ms  142.147.51.39

ACE - Expert

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35.8K Messages

2 years ago

Ah... to be honest, I got impatient and killed it when my hop 12 (the fourth non-responding hop) started spewing asterisks.  Since @tonydi got a response after 4 misses, I tried it again and let it run, and I see that I, too, get a response from 142.147.51.39 on the very next hop.  Grrr at my own impatience.

That doesn't move the needle very far because we don't know who owns those four hops that didn't respond to tonydi or myself, nor do we know where or why @bassjunky 's ICMP traffic got lost somewhere in that gap.

We do know that AT&T's network does have a route to that IP and that 2 different residential service customers from opposite ends of the country got there.

Community Support

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232.8K Messages

2 years ago

We'd be glad to help you connect to your job's VPN, bassjunky.

 

In addition to trying out JefferMC's latest suggestion, please check out our article that provides solutions and fixes for a VPN Not Working with AT&T Internet.

 

We'll be awaiting your response!

 

Aminah, AT&T Community Specialist

New Member

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5 Messages

2 years ago

Thanks for the help.  Here's the trace route when using my phone as a hotspot.  It never seemed to resolved, however, I was still able to connect to the VPN and FTP.

traceroute to (142.147.51.198), 64 hops max, 52 byte packets

 1  172.20.10.1 (172.20.10.1)  4.017 ms  2.663 ms  2.304 ms

 2  107.243.2.5 (107.243.2.5)  33.195 ms *

    107.243.2.133 (107.243.2.133)  157.460 ms

 3  * * *

 4  * * *

 5  * * *

 6  * * *

 7  12.126.193.30 (12.126.193.30)  48.285 ms  111.981 ms  35.845 ms

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Really strange.  I appreciate everyones suggestions.

ACE - Expert

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35.8K Messages

2 years ago

Well, that tells me that you use AT&T for Wireless, but that's about it.

New Member

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5 Messages

2 years ago

Correct, ATT wireless.  It's just so strange that it works through wireless, but not lan.  And the fact that it had worked for months and just suddenly stopped.  I'm hoping our IT dept. can help.  Thanks for your help.  I will post back if I ever figure it out.

ACE - Expert

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35.8K Messages

2 years ago

I will post back if I ever figure it out.

Please do.  Ask your IT department to specifically check your home IP address to make sure that it's not included in ranges in any/all places they block traffic.

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