Very Computer

by **Gary Mil** » Fri, 29 Aug 2003 11:50:15

I have an Ultra 30 at home, running Solaris 9 8/03, connected to a
Shaw Cable modem. DHCP works very nicely, even though they don't
support Solaris. The only problem I have is that there is no reverse
DNS on the IP address that it's given. There is forward DNS. Is it
possible that they expect the DHCP client to register reverse DNS?
Is there a way to do this with solaris?

--
-Gary Mills- -Unix Support- -U of M Academic Computing and Networking-

by **Rich Tee** » Fri, 29 Aug 2003 12:53:22

Quote:> I have an Ultra 30 at home, running Solaris 9 8/03, connected to a
> Shaw Cable modem. DHCP works very nicely, even though they don't
> support Solaris. The only problem I have is that there is no reverse
> DNS on the IP address that it's given. There is forward DNS. Is it

That's surprising; Shaw here have reverse IP look ups set
up like this:

Server: zen.rite-group.com
Address: 192.168.0.1

Name: h24-71-38-78.ok.shawcable.net
Address: 24.71.38.78

Quote:> possible that they expect the DHCP client to register reverse DNS?

Not likely. Why is reverse DNS so important to you? I have
the same set up as you, and improper reverse DNS doesn't cause
me any problems.

--
Rich Teer, SCNA, SCSA

President,
Rite Online Inc.

Voice: +1 (250) 979-1638
URL: http://www.rite-online.net

by **Joerg Schilli** » Fri, 29 Aug 2003 17:20:24

Quote:>> possible that they expect the DHCP client to register reverse DNS?

>Not likely. Why is reverse DNS so important to you? I have
>the same set up as you, and improper reverse DNS doesn't cause
>me any problems.

Only the onwer of the ip network address block may do reverse DNS.

This should be the IP provider. Looks like you have a lazy or incapable
IP-provider.

--

URL: http://www.fokus.fraunhofer.de/usr/schilling ftp://ftp.berlios.de/pub/schily

by **Gary Mil** » Fri, 29 Aug 2003 23:43:15

>> I have an Ultra 30 at home, running Solaris 9 8/03, connected to a
>> Shaw Cable modem. DHCP works very nicely, even though they don't
>> support Solaris. The only problem I have is that there is no reverse
>> DNS on the IP address that it's given. There is forward DNS. Is it
>That's surprising; Shaw here have reverse IP look ups set
>up like this:
>> possible that they expect the DHCP client to register reverse DNS?
>Not likely. Why is reverse DNS so important to you? I have
>the same set up as you, and improper reverse DNS doesn't cause
>me any problems.

It's not that important. I was just wondering if something was
missing from the protocol. I have noticed that whenever my IP
address changes, which is only when I change my MAC address, or
when they move me to a different subnet, that I have reverse DNS
for a while. Eventually, it disappears.

--
-Gary Mills- -Unix Support- -U of M Academic Computing and Networking-

by **Barry Margoli** » Sat, 30 Aug 2003 00:21:10

>It's not that important. I was just wondering if something was
>missing from the protocol. I have noticed that whenever my IP
>address changes, which is only when I change my MAC address, or
>when they move me to a different subnet, that I have reverse DNS
>for a while. Eventually, it disappears.

Did you leave out a word there? Did you mean to write "that I have reverse
DNS problems for a while"?

On some systems, the system they use to put customer IP assignments into
DNS takes a little while to propagate. There's nothing you can do about
it, it's part of the ISP's DHCP/DNS design.

--

Level(3), Woburn, MA
*** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.
Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.

by **Gary Mil** » Sat, 30 Aug 2003 12:03:46

>>It's not that important. I was just wondering if something was
>>missing from the protocol. I have noticed that whenever my IP
>>address changes, which is only when I change my MAC address, or
>>when they move me to a different subnet, that I have reverse DNS
>>for a while. Eventually, it disappears.
>Did you leave out a word there? Did you mean to write "that I have reverse
>DNS problems for a while"?

Nope. I meant that it is there for a while, and then disappears.
It's been gone for a long time.

Quote:>On some systems, the system they use to put customer IP assignments into
>DNS takes a little while to propagate. There's nothing you can do about
>it, it's part of the ISP's DHCP/DNS design.

I notice that today I do have reverse DNS for my home IP address.
The address hasn't changed for about a year. I'll just put it down
to quirks of Shaw's nameserver.

--
-Gary Mills- -Unix Support- -U of M Academic Computing and Networking-

by **Rob Stampf** » Sun, 31 Aug 2003 05:33:54

>>>It's not that important. I was just wondering if something was
>>>missing from the protocol. I have noticed that whenever my IP
>>>address changes, which is only when I change my MAC address, or
>>>when they move me to a different subnet, that I have reverse DNS
>>>for a while. Eventually, it disappears.

>>Did you leave out a word there? Did you mean to write "that I have reverse
>>DNS problems for a while"?

>Nope. I meant that it is there for a while, and then disappears.
>It's been gone for a long time.

>>On some systems, the system they use to put customer IP assignments into
>>DNS takes a little while to propagate. There's nothing you can do about
>>it, it's part of the ISP's DHCP/DNS design.

>I notice that today I do have reverse DNS for my home IP address.
>The address hasn't changed for about a year. I'll just put it down
>to quirks of Shaw's nameserver.

Any active IP address ought to return something in response to a
reverse DNS lookup, even if it is a generic placeholder which
essentially is just a string version of the IP address. If it
really returns nothing (NXDOMAIN), it can break (at least) ftp
and outbound email transfers. The ISP should be responsible for
this in the default, although some allow you to administer your
own reverse lookups, if you have a static IP and the technical
acumen to set up a nameserver and zone file to do so, through a
process called reverse CNAME delegation.

If rDNS is failing, it is likely that the ISP's nameservers have
a problem, and if it is consistently failing, it is even more likely
the ISP is blissfully unaware of the problem. (Obviously, it can
also be on your end, if you have requested and gotten a delegation.)

Gary, if you'd like to privately mail me your IP address, I will
take a look at it with "dig" and see if I can narrow down what is
going on.

Rob

Very Computer

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?

How to get reverse DNS with a cable modem?