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Old 07-25-2013, 10:51 PM   #16
Ser Olmy
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More firewall issues, perhaps?

Try querying one of Google's public DNS servers over IPv6:
Code:
nslookup www.linuxquestions.org 2001:4860:4860::8888
 
Old 07-25-2013, 10:53 PM   #17
Soapm
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Code:
me@lenny:/# nslookup www.linuxquestions.org 2001:4860:4860::8888
Server:         2001:4860:4860::8888
Address:        2001:4860:4860::8888#53

Non-authoritative answer:
Name:   www.linuxquestions.org
Address: 75.126.162.205
 
Old 07-25-2013, 11:00 PM   #18
Ser Olmy
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So no firewall issues then. It means that the following commands really ought to work as well:
Code:
nslookup www.linuxquestions.org 2001:558:feed::1

nslookup www.linuxquestions.org 2001:558:feed::2
If they don't, Comcast is to blame and you'll have to use a different DNS server.
 
Old 07-25-2013, 11:02 PM   #19
Soapm
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Looks like they work???

Code:
me@lenny:/# nslookup www.linuxquestions.org 2001:558:feed::1
Server:         2001:558:feed::1
Address:        2001:558:feed::1#53

Non-authoritative answer:
Name:   www.linuxquestions.org
Address: 75.126.162.205
 
Old 07-25-2013, 11:15 PM   #20
Ser Olmy
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It sure does. But you still can't resolve names?

Does ping6 www.google.com still return an error? If it does, try this:
Code:
~$ nslookup
> server
Default server: what does it say here?
Address: and here?
[... more servers may be listed here ...]
> exit
 
Old 07-25-2013, 11:26 PM   #21
Soapm
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Looks like ip4 is working but ipv6 is not.

Code:
me@lenny:/# ping6 www.google.com
unknown host
me@lenny:/# nslookup
> www.google.com
Server:         68.87.85.98
Address:        68.87.85.98#53

Non-authoritative answer:
Name:   www.google.com
Address: 208.117.232.86
Name:   www.google.com
Address: 208.117.232.89
Name:   www.google.com
Address: 208.117.232.87
Name:   www.google.com
Address: 208.117.232.82
Name:   www.google.com
Address: 208.117.232.90
Name:   www.google.com
Address: 208.117.232.91
Name:   www.google.com
Address: 208.117.232.80
Name:   www.google.com
Address: 208.117.232.83
Name:   www.google.com
Address: 208.117.232.84
Name:   www.google.com
Address: 208.117.232.88
Name:   www.google.com
Address: 208.117.232.81
Name:   www.google.com
Address: 208.117.232.85
> exit
 
Old 07-26-2013, 12:22 AM   #22
Ser Olmy
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Quote:
Originally Posted by Soapm View Post
Looks like ip4 is working but ipv6 is not.

[CODE]me@lenny:/# ping6 www.google.com
unknown host
me@lenny:/# nslookup
> www.google.com
Server: 68.87.85.98
Address: 68.87.85.98#53

Non-authoritative answer:
Name: www.google.com
Address: 208.117.232.86
Actually, it looks like:
  • Your system is in fact not using the name servers in /etc/resolv.conf (2001:558:feed::1 and 2001:558:feed::2), but 68.87.85.98 instead. This could be a cache issue, is nscd running on your system? It also shouldn't be a problem, but...
  • The 68.87.85.98 name server seems to have been configured not to return IPv6 AAAA records. You can run nslookup -q=AAAA www.google.com. 68.87.85.98 to confirm this.
Normally, you don't have to query a DNS server over IPv6 in order to resolve AAAA records. In this case, however, it seems Comcast have configured their IPv4 DNS servers to return only IPv4 A records, probably to prevent customers with non-functioning IPv6 setups from experiencing hangs and delays as their browsers try to reach IPv6 addresses.

If you can just get rid of the old DNS server settings, everything should work fine.
 
Old 07-26-2013, 10:41 AM   #23
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We lost power last night and I couldn't get my server to boot. I hooked a monitor to it and noticed it was stopping at getting an IP address so I used a live CD then commented out the IPv6 portion of the interface file and it was then able to fully boot.

This is how the file looked with IPv6 commented out.

Code:
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
        address 192.168.0.199
        network 192.168.0.0
        netmask 255.255.255.0
        broadcast 192.168.0.255
        gateway 192.168.0.1
# iface eth0 inet6 dhcp
The best I can tell by reading on the internet, if I want to "double stack" without tunneling then I should do something like "eth0:1" or that perhaps my network adapter doesn't support IPv6 but all of the info looks dated and I can't find how to test an adapter for IPv6 support.

Was my above interface entries causing a conflict by having both IPv4 and IPv6 on eth0? I have to wonder if this was my problem.
 
Old 07-26-2013, 11:23 AM   #24
Ser Olmy
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Quote:
Originally Posted by Soapm View Post
We lost power last night and I couldn't get my server to boot. I hooked a monitor to it and noticed it was stopping at getting an IP address so I used a live CD then commented out the IPv6 portion of the interface file and it was then able to fully boot.
Your distribution seems to hang if an interface is set to obtain an IPv6 address via DHCP and the DHCP service isn't responding. If this can be reproduced, I'd file a bug with Debian.

There could be several reasons why there was no response from the DHCP service. Perhaps your router settings reverted to defaults because of the outage, or the router's own DHCP client didn't receive an IPv6 address from upstream within the timeout period.

Quote:
Originally Posted by Soapm View Post
The best I can tell by reading on the internet, if I want to "double stack" without tunneling then I should do something like "eth0:1" or that perhaps my network adapter doesn't support IPv6 but all of the info looks dated and I can't find how to test an adapter for IPv6 support.
You do not have to use aliases for IPv6. Actually, aliases are deprecated and shouldn't be used at all, but in any case they have nothing to do with using different protocols. IPv4 and IPv6 are separate Layer 3 protocols and never cross paths, and enabling both cannot cause a conflict. The same goes for other Layer 3 protocols such as IPX and AppleTalk.

It's impossible for a NIC not to support IPv6 (or any other layer 3 protocol). The NIC talks to the network medium, the driver talks to the NIC, and the TCP/IP stack in the OS talks to the driver. The NIC and the driver have no concept of "protocols", they deal with Ethernet frames. (Exception: Many NICs provide extra services such as TCP checksum offloading, but it's up to the IP stack to make use of them through the driver.)
 
Old 07-26-2013, 12:54 PM   #25
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Ok, thanks for your expertise... I changed IPv6 to static and all seems to be working now. The router is actually the Comcast modem (TG862) and I've had to reboot that thing so many times it's frustrating. I will purchase a router once I get the working figured out so I know what to look for.

Code:
 iface eth0 inet6 static
        address 2601:1:87c0:3c::10
        netmask 64
The site I got that from also shows a gateway of like "gateway 2001:db8::1ead:ed:beef" which I know is an example but I don't find a gateway in my router or on any of my windows machines. Do I need a gateway for best operations and if so how do I find it?

also, making progress on ping6. It resolved the name even if it isn't returning any packets. And progress is a good thing! Thanks again.

Code:
me@lenny:/# ping6 www.google.com
PING www.google.com(2404:6800:4003:802::1011) 56 data bytes
Code:
me@lenny:/# nslookup -q=AAAA www.google.com. 68.87.85.98
Server:         68.87.85.98
Address:        68.87.85.98#53

Non-authoritative answer:
www.google.com  has AAAA address 2607:f8b0:4007:800::1011

Authoritative answers can be found from:
 
Old 07-26-2013, 01:00 PM   #26
Soapm
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ps...

I also noticed I get this same hanging when I ping Comcast DNS servers. This might be a Comcast problem and not something with my machine. This is all I get;

Code:
me@lenny:/# ping6 2001:558:feed::1
PING 2001:558:feed::1(2001:558:feed::1) 56 data bytes
^C
--- 2001:558:feed::1 ping statistics ---
110 packets transmitted, 0 received, 100% packet loss, time 109872ms
 
Old 07-26-2013, 01:10 PM   #27
Ser Olmy
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Quote:
Originally Posted by Soapm View Post
Code:
 iface eth0 inet6 static
        address 2601:1:87c0:3c::10
        netmask 64
The site I got that from also shows a gateway of like "gateway 2001:db8::1ead:ed:beef" which I know is an example but I don't find a gateway in my router or on any of my windows machines. Do I need a gateway for best operations and if so how do I find it?
The gateway is the next-hop router, the router that provides a means for packets to be sent to hosts in networks other than your own. In your case, the gateway for your PCs will be the IP address of the router/modem. The modem's gateway will be the next upstream router and so on.

As I mentioned earlier, IPv6 has two mechanisms called Router Advertisement and Router Solicitation. Using these mechanisms, a host can automatically identify routers on the local network, so normally you don't have to specify a gateway.

For this mechanism to work, your PC/server must accept Router Advertisements. This is controlled by /proc/sys/net/ipv6/conf/<interface>/accept_ra. I believe you turned that on previously, but if the default setting in your distribution is not "1", it may have reverted to 0 after the reboot.

Quote:
Originally Posted by Soapm View Post
also, making progress on ping6. It resolved the name even if it isn't returning any packets.
Try traceroute6 www.google.com to see how far it gets.
 
Old 07-26-2013, 01:57 PM   #28
Soapm
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Thanks, but I hit another brick wall and need to take a break. I'm about to go crazy with this thing.

Turns out Linux will use IPv6 static just fine but Windows, especially my XP machine refuses to cooperate. They want DHCP which Linux seems to have a problem with. And since the router won't let me reserve a IPv6 address to a MAC address it keeps giving out the Linux address to a Windows machine. I guess I could assign the Linux box an IP outside the DHCP range???

I this the right entry "iface eth0 inet6 dhcp".
 
Old 07-26-2013, 05:08 PM   #29
Soapm
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The engeneer on the Comcast forum got it working, he had me switch the static address to

Quote:
2601:1:8780:1db::10/64
Code:
me@lenny:/# ping6 www.google.com
PING www.google.com(2404:6800:4007:801::1014) 56 data bytes
64 bytes from 2404:6800:4007:801::1014: icmp_seq=1 ttl=48 time=236 ms
64 bytes from 2404:6800:4007:801::1014: icmp_seq=2 ttl=48 time=249 ms
64 bytes from 2404:6800:4007:801::1014: icmp_seq=3 ttl=48 time=235 ms
64 bytes from 2404:6800:4007:801::1014: icmp_seq=4 ttl=48 time=235 ms
^C
--- www.google.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3000ms
rtt min/avg/max/mdev = 235.199/239.068/249.129/5.858 ms
So much too learn about IPv6 and how you guys came up with those addresses?????
 
  


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