how-to block ads
|
jfeise
join:2009-03-27
Santa Ana, CA
| AT&T 4to6 relay not working? I have been trying to set up IPv6 on my Linux box which is connected to an AT&T DSL line.
However, it seems that the 192.88.99.1 address is not reachable for me.
A traceroute shows it hanging between AT&T and HE.net:
$: traceroute 192.88.99.1
traceroute to 192.88.99.1 (192.88.99.1), 30 hops max, 38 byte packets
1 192.168.0.1 (192.168.0.1) 0.410 ms 0.309 ms 0.221 ms
2 adsl-75-3-255-254.dsl.irvnca.sbcglobal.net (75.3.255.254) 6.155 ms 6.352 ms 6.410 ms
3 dist1-vlan60.irvnca.pbi.net (67.114.48.130) 5.573 ms 6.772 ms 6.567 ms
4 bb1-p2-1.ksc2mo.sbcglobal.net (151.164.42.7) 82.854 ms 197.457 ms 6.565 ms
5 ex1-p13-0.eqlaca.sbcglobal.net (151.164.188.138) 75.613 ms 163.004 ms 210.869 ms
6 asn6939-he.eqlaca.sbcglobal.net (151.164.251.86) 7.742 ms 7.306 ms 7.577 ms
7 10gigabitethernet1-3.core1.pao1.he.net (72.52.92.21) 27.105 ms 25.722 ms 28.047 ms
8 * * *
I can receive IPv6 pings from the outside, I see them with tcpdump.
My thoughts are that either the DSL modem (a Siemens Speedstream 4100) drops outgoing packets with the IPv6 protocol (41) or that somewhere within AT&T there is an issue.
Somebody with contacts at HE.net told me yesterday that they don't see any packets from me.
I've also written about it on my blog: »www.feise.com/~jfeise/blogs/inde···6?blog=8
Does anybody have an idea what could be causing this problem?
TIA. | |
|  
Datlev
Premium
join:2002-02-15
Ashburn, VA
 ·Vonage
 ·Verizon FIOS
| Re: AT&T 4to6 relay not working? A couple of pointers:
0) The specific ipv6 transition technology you are talking about is called 6to4 (not 4to6) »en.wikipedia.org/wiki/6to4. Many providers (including my ISP Verizon) do not provide 6to4 relays, so AT&T is not alone in this. Through the use of anycast, the closest relay is automatically chosen, but may not be terribly close, and may very from time to time.
1) Just because you can not traceroute to it, does not mean that the host is unreachable by all protocols. traceroute implementations can use tcp, udp, and/or icmp depending on OS, and flags passed. Many providers (or specific routers) will block (or deprioritize) specific icmp messages as well.
See also: »en.wikipedia.org/wiki/Traceroute
2) If you are serious about trying IPv6, my personal recommendation would be to look into a tunnel broker rather than using 6to4 or teredo. In my experience, you will see much better reliability. I happen to use and recommend the free sixxs.net tunnels, but just google "ipv6 tunnel broker" to see some of the options available.
Good Luck. | |
| | jfeise
join:2009-03-27
Santa Ana, CA
2 edits | Re: AT&T 4to6 relay not working? Yes, I know that it is called 6to4. It just stroke me as illogical, since on my side it is IPv6 to IPv4, and on the other side, it is 4 to 6.
Anyway, I tried to use the HE.net tunnel broker as well. And that doesn't work, either.
And the fact that AT&T is not alone in it only points to the sad state of things. They have a web page about providing IPv6, at least to the US government, including DSL access, though.
And I also know very well that a traceroute is not the definitive way to determine reachability. It is just the only tool available to _me_. I don't have personal connections into telcos. | |
| | |
Datlev
Premium
join:2002-02-15
Ashburn, VA
·Vonage
·Verizon FIOS
| Re: AT&T 4to6 relay not working? If you are willing to give it another try, I'm sure that someone here will be willing to help troubleshoot your he.net protocol 41 tunnel (aka 6in4 tunnel). It has been awhile since I used he.net, but their forums are probably the best place to start.
The most common problem with proto 41 tunnels are getting the local NAT to properly forward packets. (In your case, this may be your DSL modem and/or an additional router) »en.wikipedia.org/wiki/6in4
1) Do you have a static ipv4 address ? If not, then you may want to ensure that your current EXTERNAL ipv4 address is properly registered with he.net, and setup a script to automatically update he with your correct address. See »www.tunnelbroker.net/forums/inde···3#msg663
2) Does your DSL Modem do NAT, or do you have another device after the modem (router of some sort) ? What is the brand/model ?
3) Configure your NAT to forward protocol 41 to the internal ipv4 address associated with your linux machine. If you do not have the option for protocol 41 forwarding, try setting the linux machine into the DMZ for your NAT/Router.
4) Read »www.tunnelbroker.net/forums/inde···pic=18.0 for the sample linux configuration steps.
Good Luck. | |
| | | | jfeise
join:2009-03-27
Santa Ana, CA | Re: AT&T 4to6 relay not working? As it turns out, my Web hoster just announced that they are going to test IPv6, so I should be able to get a v6 address for my Web machine (also Linux). I'll test a tunnel with that then, which gives me the ability to control both endpoints. | |
| | | | | charlesnw
join:2008-05-28
El Monte, CA | Re: AT&T 4to6 relay not working? Who do you use as your slice provider? | |
| | | | | | jfeise
join:2009-03-27
Santa Ana, CA
| Re: AT&T 4to6 relay not working? said by charlesnw  :Who do you use as your slice provider? My provider is a company called grokthis.net, out of Philadelphia. | |
| jfeise
join:2009-03-27
Santa Ana, CA
| I now figured out that the problem was the Siemens Speedstream 4100 DSL modem that SBC/AT&T provides to DSL subscribers. That modem seems to block the IPv6-tunneled packets.
Siemens has exited the DSL modem business, and there are no firmware updates available. Also, SBC apparently has their own configuration, which together cripples this modem.
I bought a D-Link DSL-2320B today, and I can tunnel IPv6 just fine through it (it has another issue, though, only giving out the IP address for around 15 seconds...) | |
| | jfeise
join:2009-03-27
Santa Ana, CA
| Re: AT&T 4to6 relay not working? An update: I returned the D-Link, after even their tech support couldn't help with the 15-second DHCP lease renew time, and after a detour with a Motorola 2210 which blocks incoming pings, I ended up with a 2-Wire 2701 which seems to be way less crippled than all the other DSL modems. Finally a manufacturer who doesn't think everybody is stupid... | |
| | awasser1
join:2004-03-30
Bloomfield, CT
| Yep the SpeedStream 4100 does not work with IPV6. I found that out after three weeks. I switched to the UWire one I had and it seems to work better. I am still trying to make everything work with windows 7 and server 2008 R2. The server works on ipv6 just fine but the pc computer still tries to pickup ipv4 first. when u put ping -6 it works ok. so i am still trying to fix it.. fun fun fun.
Alec | |
| | |
Datlev
Premium
join:2002-02-15
Ashburn, VA
·Vonage
·Verizon FIOS
| Re: AT&T 4to6 relay not working? said by awasser1 : I am still trying to make everything work with windows 7 and server 2008 R2. The server works on ipv6 just fine but the pc computer still tries to pickup ipv4 first. when u put ping -6 it works ok. This is usually caused by windows not *thinking* there is a valid global ipv6 address and route associated with an active network interface.
[snippet from MSDN]
DNS Query Behavior
The DNS Client service in Windows Vista has been designed to minimize the impact on DNS servers when performing DNS name queries through the following behavior:
-If the host has only link-local or Teredo IPv6 addresses assigned, the DNS Client service sends a single query for A records.
-If the host has at least one IPv6 address assigned that is not a link-local or Teredo address, the DNS Client service sends a DNS query for A records and then a separate DNS query to the same DNS server for AAAA records. If an A record query times out or has an error (other than name not found), the corresponding AAAA record query is not sent.
[/snippet]
See here: »technet.microsoft.com/en-us/libr···035.aspx
You can see if this is indeed the case by using wireshark or netmon to examine the dns queries/responses.
Good Luck.
--Dave | |
| | | |
|
