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Hi,



Since a couple of days I am having issues with my VPN connection. it uset to work flawless, but that suddenly changed. The Kundenservice advised me to write an email to info@o2online.de. But that email address does not work..



It concerns a connection between 2 fritz!boxes. The VPN connection uses IPSEC. The connection is made, however I cannot send files. This is extremely annoying since I cannot work from home right now. I have the feeling that UDP packets do not arrive. 



In the past I experienced the same issue using an PPTP vpn connection. Could this be an issue after a firmware update of the O2 router? 



I hope to get an aswer soon, I need this connection  for my work.



Thanks in advance,



Erwin



Hi Erwin,



 



I would say that a firmware update on the o2 router might cause these problems (although it should not).



 



How are the Fritzboxes connected to the internet? Does the one that runs behind the o2 router establish an own internet connection via PPPoE-Passthrough? If not that might help.



 



regards



nemesis03



The fritz!box is directly connected to the O2 box 6431.



firmware version 1.01.23b



Under PPPoE it says 'Ihr Gerät ist bereits mit allen notwendigen Einstellungen vorkonfiguriert.'



uPNP is activated



ports opened 



Benutzerdef.192.168.1.3Alle/Alle1-160/163-8889http://192.168.1.1/images/icon_ok_h15.gif

 



This results in an established connection. But not being able to recieve any data.



 



It seems O2 is doing something. The Kundenbetreuung is totally incompetent and just reads a script. And I can't even send an email to a technical person. And still 18 month to go on the contract.... 



Can you try to replace the 6431 trough the Fritzbox? You will only be able to use the internet, telephony will be impossible. (If you can’t make it work, please ask)



If VPN works without the 6431, you know the reason.



the firmware version 1.01.23b tells me that you have a bitstream connection (a VDSL-port that is owned by Telekom) that does not allow PPPoE-Passthrough.



 



Which Fritzbox do you have? If it is a Fritzbox with a VDSL-modem you might test the connection while connecting the Fritzbox directly to the telefone line (without the 6431).



 



Were there recently any changes in the configuration? Maybe at the other end of the connection?



 



 



 



The firtz! is a 7170. So connecting it directly is not an option. 



No changes in the config. And it was running reliably. suddenly it did not work anymore. a couple of months ago this happened to a PPTP vpn connection that I had running stable for months.



 



I feel there is a conspiracy going on!!



 



Anyway, i does not work anymore. And it could be either O2 or telekom. It is getting complicated. 



 



Is there a reliable and good VDSL provider in Berlin that is not driven by commercial goals?



 



E



I have read that some people are having problems when they do a port-forwarding for the ports beyond 1024. Maybe you can delete the port-forwarding and try again.



 



And you can try to do a factory reset on the 6431 and then configure it again.



 



And you might install Freetz on the Fritzboxes and try to establish an openvpn-tunnel. But that is a lot of work.



 



I think it will be hard to find a good VDSL provider that ist not driven by commercial goals.



Good suggestions, I already did the reset. The alternative I use right now is via SSL. however streaming of media is not possible via this connection. 



 



I tried openVPN (pc to pc) in the past, but that did not work.



 



The VPN link was to the Netherlands. There I have a provider called XS4ALL. I guess the name says it all... Extremely flexible, a lot of great and new initiatives, and amazing customer support. And a 100mbit up/down glasfiber connection! 



 



 



Now I'm running out of ideas.



Can you test your Fritzbox from another (v)dsl line, maybe using the one of your neighbor?



 



Maybe someone in the ip-phone-forum can help you: http://www.ip-phone-forum.de/forum.php



There is a section for o2 and a section for avm. I think the avm-section would be the better choice.



I have been playing around this weekend. The VPN connection was setup again and connection is realised. Still the 



 



So I tried it with the Fritz vpn software for windows. VPN connected well, but throughput is 2kb/s. 



 



So I tried an alternative. Bittorent sync, which worked fine in the past. it connected well, but throughput is 2kb/s. 



 



So I see a pattern and that is that any program using UDP is blocked. 



 



So I tried Webdav, since this is uses TCP. And that confirmed that my UDP ports are blocked, since downloads went up to >1Mb/s.



 



Now I saw that since January 7, the fair use policy has been changed. That could well be the reason. if you use more than a certain volume, your download speed is reduced. I received no notification or nothing. I am shocked that this is allowed in Germany. I will try to cancel my connection asap.



 



 



 



 



 



 



 



 



 



E-berliner schrieb:

Now I saw that since January 7, the fair use policy has been changed. That could well be the reason. if you use more than a certain volume, your download speed is reduced. I received no notification or nothing. I am shocked that this is allowed in Germany. I will try to cancel my connection asap.



I don't think that's the problem, because in the fair use policy grants 2Mbit/s and the fair use policy will be activated on 01.07.2014 (*click*), so it is not active yet.



 



Please contact the moderators with a private message to o2_dsl (*click*). Maybe they have an idea what's going on. Don't forgive your account number and you personal password and give them the link to this thread so they can see what you have already tried.



Miracles happen. Since about 30 minutes the connection is back and downloads are possible. VPN works again as well as bittorrent sync. Still the speed is very low; <250kb/s.



 



What is going on here????



 



And now it's gone again....



 



https://



Did you send a private message to o2_dsl? Then lets wait for their answer.



Yep, I send them a message. Yesterday. No reaction whatsoever sofar. So I keep waiting....



 



Pretty nice to see that suddenly the connection came up again. I hope it lasts for ever!



 



https://



https://



That did not last long.... 7 minutes



Can you provide an indication on how long I have to wait for an answer? I have not recieved a message that they have received my email.



 



Thanks



Complicated questions (and this is a complicated question) can take a few days. Did you look in the Posteingang whether there is an answer (by default there is no email notification)? And when you go to Gesendete Nachrichten and click on your message you can see whether an when the message has been read.



So this is the reaction 



 



"I'm really sorry, but we can't help u here in this case.



 



Normal connection works, if u got trouble with vpn etc. you have to solve this by your own, im sorry 😢  



 



Regards, Matze "



 



In short 



1. The provider does not provide a functioning internet connection. 



2. The helpdesk is completely incompetent and can only read a script



3. The forum mentiones the same issue many times without a solution



4. There is no way I can reach a technical helpdesk



 



In conclusion, I am stuck with a **bleep**ty connection and a contract until August 2015. O2 - the worst provider ever



 



 



That is bad luck.



In the moment we do not know where the problem really ist. It might be




  • the 6431 blocking UDP-traffic, but I'm wondering why you are the only one that is having difficulties
  • the "o2-VDSL-servers" that block UDP-Traffic or the ports
  • one of your Fritzboxes that is faulty
  • the ISP on the other end of the ISP that is somehow blocking something
  • a server somewhere on the route that is faulty
I think if the 6431 or the o2-servers are blocking UDP-traffic on purpose, then there shouldn't be times when the connection is working.



 



Maybe you should just by a vdsl-modem and see whether that solves your problem. Of course you cannot use the telephone line while you are using another vdsl-modem (unless you read-out the sip-account-information).



 



And you cannot expect the helpdesk to give you enterprise-support on a highly complicated question. I think there are companys that will give you enterprise-support, but they are much more expensive than the 30-40 Euro per month you pay o2.



 



And at the moment there is no proof that o2 is at fault.



Did you already try to establish a vpn-connection using a neighbors internet connection?



Did you already try to lower the mtu-value for the vpn-tunnel? Here is a posting where a user had a similar problem (with OpenVPN) and manged to fix this for a short time: *Klick*



Maybe you can ask him whether he found a permanent solution.



I checked the connections. I can't even ping the destination via UDP; however i can via TCP. I checked various port ranges. TCP is open, UDP is closed. 



 



The MTU is only relevant for the size of the packets sent over the internet. The higher the MTU, the faster the connection. But also I higher risk of packets not arriving.



 



In my case all UDP ports are blocked. I traced the packages and these are stopped in the O2 infrastructure. For 2 weeks there was no issue. VPN worked flawless. And I never change a working configuration. 



 



O2 is blocking UDP trafic.



 



O2 needs to unblock the UDP trafic



 



It is soooo simple. O2 solve my issue.



E-berliner schrieb:

I checked the connections. I can't even ping the destination via UDP; however i can via TCP. I checked various port ranges. TCP is open, UDP is closed. 



Maybe there is only an echo over TCP but not over UDP. Did you also try this from a not-o2-connection? If your theory is right then the ports should be open when you use another ISP.



The MTU is only relevant for the size of the packets sent over the internet. The higher the MTU, the faster the connection. 



The MTU is also relevant if packets are too large and have to be fragmented to be send over the internet. That might cause problems, if fragmentation is prohibited. And I think the maximum MTU on the internet is 1500 including all headers. So a MTU of 1550 would be slower than for example 1450, because the packets would be fragmented.



In my case all UDP ports are blocked. I traced the packages and these are stopped in the O2 infrastructure. For 2 weeks there was no issue. VPN worked flawless. And I never change a working configuration. 



This is the first time that you mention a trace. Can you please post the traces and the pings you did and tell us with which programs you did them.



 



If you want you can send me the address of your server in a private message and I will try the same tests from my internet line and maybe from my university (if I have access to the required programs).



nemesis03 schrieb:Maybe there is only an echo over TCP but not over UDP. Did you also try this from a not-o2-connection? If your theory is right then the ports should be open when you use another ISP.



I have no issues when I go via another provider.





The MTU is also relevant if packets are too large and have to be fragmented to be send over the internet. That might cause problems, if fragmentation is prohibited. And I think the maximum MTU on the internet is 1500 including all headers. So a MTU of 1550 would be slower than for example 1450, because the packets would be fragmented.



The optimal MTU for my connection is 1420.





This is the first time that you mention a trace. Can you please post the traces and the pings you did and tell us with which programs you did them.



 



If you want you can send me the address of your server in a private message and I will try the same tests from my internet line and maybe from my university (if I have access to the required programs).



I used netscan pro. ping on port 80. A website is running on this port and can be reached.



TCP results



Pinged xxx.homeserver.com 82.161.xxx.xxx] with SYN packets.

Start Time: Sun, 26 Jan 2014 16:44:36

ANALYSIS:Target reached by one or more packets.

Outgoing Packet DS Bits: 000 000 ECN: 00

5 packets transmitted, 5 packets received, 0% packet loss

Round Trip Time - min/avg/max = 83.407/85.019/87.019 (ms)



 



ICMP results



Pinged xxx.homeserver.com m82.161.xxx.xxx] with 32 data bytes

Start Time: Sun, 26 Jan 2014 16:56:37

ANALYSIS:Target reached by one or more packets.

Outgoing Packet DS Bits: 000 000 ECN: 00

5 packets transmitted, 5 packets received, 0% packet loss

Round Trip Time - min/avg/max = 65.827/78.049/94.394 (ms)



 



UDP results



Pinged xxx.homeserver.com c82.161.xxx.xxx] with 32 data bytes

Start Time: Sun, 26 Jan 2014 16:57:26

ANALYSIS:Target not reached. Press Settings and try increasing TTL and Timeout values.

If that does not help, the target might have an ICMP filter in place or be offline.

Outgoing Packet DS Bits: 000 000 ECN: 00

5 packets transmitted, 0 packets received, 100% packet loss



 



 



 



 



 



I could not find the netscan pro which produces this output, but there are several programs with similar names. Can you provide a link?



 



Can you please also post the trace.



 



If you can prove that on o2-server is blocking the udp-traffic there might be a chance that a ticket for the technical support will be opened.



 



It would be interesting if it is only this server that is blocking udp-traffic. There is a chance that traffic from my dsl-connection in Hamburg will not go through this server, so maybe udp-traffic from my connection will not be blocked (or blocked by another server).





If you can prove that on o2-server is blocking the udp-traffic there might be a chance that a ticket for the technical support will be opened.



 



It would be interesting if it is only this server that is blocking udp-traffic. There is a chance that traffic from my dsl-connection in Hamburg will not go through this server, so maybe udp-traffic from my connection will not be blocked (or blocked by another server).



I am getting confused now. So there is a technical support??? So far I have only received a reaction from a moderator named Matze who clearly is not willing to provide any help in any way.



 



The point is that it suddenly stopped working, whereas it was working before. I did not make any changes to the setup. 



 



If you are routed via another server it might well be possible for the time being. However that does not solve my issue. It still could be that silly router that O2 provides, but replacing it with another one will make me loose the telephone line. 



 



In short, O2 is not delivering a working internet connection and does not provide any customer service. O2 is the worst provider ever and does not provide any customer service. 



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