ipv6 questions

dmacleo

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Jun 21, 2012
Messages
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so I have a block of ipv6
2604:4300:a:b::1/64

so to add them I keep netmask left as it is 255.255.255.0 and just start adding like this?
2604:4300:a:b::0000:0000:0000:0001
2604:4300:a:b::0000:0000:0000:0002
2604:4300:a:b::0000:0000:0000:0003
etc.

I am confused on how ipv6 is allocated to domains (which # to use) and on how to actually add to DA. I see conflicting info on the netmask entry.
 
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yeah been reading that one too.
t
his line is what is catching my eye
Note that the netmask 255.255.255.0 only applies for IPv4 IPs and will be ignored here.
The IPv6 mask format, eg: /64 is not yet supported.
I don't know of the guide is outdated or not
 
Hello,

The /mask only applies to the network.. which other IPs it can see in that subnet... and in reality, I believe that the system uses the netmask of whatever the default IP in the device is... making that field somewhat pointless in many cases.

If you're just looking for a fast way to add all of the IPs in one (or far fewer) clicks, you could add this IP, for example:
Code:
2604:4300:a:b:0:0:0:1-10
which would add 10 IPv6 IPs.
I will admit that I don't think you can use an octal range.. (that implementation is missing)... but hopefully this helps.

John
 
will try that thanks,
first need to learn how to actually add them to centos, every guide seems different so I am trying to make sure I do when I have kvm handy.
 
I hope the following adds a little clarity to the whole concept of what a netmask[/] is for and what it does.

The entire and only purpose of a netmask is to let the networking system built into your OS know whether another IP# is local to your network, or not. Why? Because on the packet level, networks route internal and external IP#s differently. I'm going from memory here, and my knowledge comes from reading one of the early revisions of the DNS and Bind book published by O'Reilly.

The netmask defines whether a packet should be routed internally or externally (to the network, not jut the server) because internal routing is not done by IP# at all on the packet level, but rather by keeping a table of NIC numbers (mostly for purposes of speed and to put less load on border routers. While most of us don't give it much thought, somewhere upstream from the router in your cabinet at the datacenter is a huge border router responsible for keeping track of much of the Internet.

So the bottom line is that the netmask only needs to be correct for the IP#s your server uses to send out packets (generally only the main IP#) land even then only if you've got other machines in your LAN which your server should be able to contact (for example if your datacenter charges you for all data leaving your cabinet or their border router).

Someone feel free to correct me if I've made mistakes :).

Jeff
 
thats always the way I have understood it, my confusion here with this was the actual DA data entry. some saying you have to enter something there and others saying don't.
basically conflicting info.
and where I was having issues both ways (due to me incorrectly thinking the range had already been added to actual server) I got to wondering if this was my issue.
 
You're nowhere as confused about IPv6 as I am :). My (extremely limited) understanding of IPv6 is that the netmask is supposed to be easier to configure.

I'm certainly willing to let John be the final arbiter of how DirectAdmin implements IPv6; I just wanted to do a bit of background explanation for the forum record.

Jeff
 
You're nowhere as confused about IPv6 as I am :). My (extremely limited) understanding of IPv6 is that the netmask is supposed to be easier to configure.

I'm certainly willing to let John be the final arbiter of how DirectAdmin implements IPv6; I just wanted to do a bit of background explanation for the forum record.

Jeff

heh, in a battle of confusion I seldom lose :P
my strong points are my stupidity :)
got the dual php running ok now so I guess I start in on adding the ipv6 addresses to centos.
any advice/guides on the adding to server would be appreciated as I see a few written using different methods.
 
having a lot of issues with this.
whenever I have an ip4 and ipv6 assigned to a domain apache will not start.
I thought DA allowed both to be assigned (I am not talking about linking ipv6 to 4) to a domain.

error is
(EAI 2 )Name or service not known: AH00547: Could not resolve host name (my shared ipv4 ip listed here)
 
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Typically, the hostname should be in:
/etc/hosts

with the server IP, eg:
Code:
1.2.3.4  server.hostname.com
Several services rely on this entry, including exim, apache and proftpd.

John
 
Typically, the hostname should be in:
/etc/hosts

with the server IP, eg:
Code:
1.2.3.4  server.hostname.com
Several services rely on this entry, including exim, apache and proftpd.

John

hosts does have the ipv4 ip in it in that format.
should there be an ipv6 address there too?
issue only happens if I have domain with ipv4 and ipv6 ip assigned.
if only ipv4 or only ipv6 seems ok (well ipv4 is ok for sure) with limited testing.
 
Very strange.. not sure what's causing it (no other reports of this before).

In any case, it wouldn't hurt to try adding the IPv6 to the /etc/hosts file as well.
Everything I Google all seems to point to /etc/hosts.

John
 
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