Bug 211800

This is not an iptables problem. It is a confugration problem.

Assigning to anaconda.

We needed to be writing out the ::1 entry in /etc/hosts as
localhost6.localdomain6 localhost6.

Fixed in rawhide.

There is a line for 127.0.0.1 localhost, but the IPv6 entry is after it and you
hit a conflict.

  As someone not familiar with IPv6, what should the exact contents of
/etc/hosts be?  The hostname localhost was not recognized on my box, so I looked
at /etc/hosts and saw a single line

::1    localhost.localdomain     localhost

so I changed it to

127.0.0.1       localhost.localdomain   localhost

Should there be two lines, like this?

127.0.0.1       localhost.localdomain        localhost
::1                   localhost6.localdomain6   localhost6

There's no real answer to this question.  The basic rule is that the name
'localhost' must be reserved for 127.0.0.1 on IPv4.  Always.  If you give the
name 'localhost' an IPv6 address or any other IPv4 address, things will break.

You don't really need an entry for ::1, but we do it for consistency.  The
localhost6 name seems to be common across other operating systems and it's good
enough for me because some people want an entry for ::1 in /etc/hosts.  If you
think of a better name for the IPv6 localhost address, let me know.  I'll be
happy to change it.

Personally, ::1 is easier to me than any name since it's so short anyway.  :)

In reference to comment #2:
There is a line for 127.0.0.1 localhost, but the IPv6 entry is after it and you
hit a conflict.

That was not the case in my situation,i.e., the entry referring to
127.0.0.1 localhost.localdomain localhost was absent in my /etc/hosts file.
Or, does the conflict somehow remove that line, leaving only the reference to IPv6?

I'm not sure how you installed because a line for 127.0.0.1 will _always_ be
written to /etc/hosts, regardless of your network settings.

Can you explain in detail how you installed?

Thanks.

  After I did a clean install, I ran system-config-network to configure a new
network interface.  I suspect that this modified the file, as in bug #140997,
which is still not fixed as far as I know.  The way to tell is to look at the
modification time of /etc/hosts and compare to when the install was done.

In my case, I did a clean install, and selected dhcp for the network settings.
After the install, I did not change any network settings, nor invoke any tools
to modify the settings. I more or less went straight to www.webmin.com,
downloaded the rpm and installed the control panel via the gnome installation
tool, by clicking on the rpm and following thru on the prompts.
I could not tell you the difference between the install time and the time stamp
on the /etc/hosts file, as I was not looking for that. Unfortunately (or
fortunately) I added the "127.0.0.1 localhost.localdomain localhost" line,
thereby modifying the time stamp.
But this is more or less the same phenomena as Andre had. 

Some additional info:
I have Verizon as my service provider and use a Westell Model 327W residential
gateway. Its DNS service is enabled and general settings use the 192.168.1.1 IP
as gateway and dns server. I don't think that it is IPv6 aware...the search
domain returned is "myhome.westell.com".
Hope that rounds out the info from my previous post.

  I can clear up some of the mystery.  I have another box on which I did a clean
of install of FC6 and no network configuration.  /etc/hosts had a timestamp
during the time of install, and looked like this:

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1               localhost.localdomain   localhost
::1             localhost.localdomain   localhost

  Then I used system-config-network to configure an xDSL interface.  Upon saving
my changes and exiting, /etc/hosts was modified to look like this:

# Do not remove the following line, or various programs
# that require network functionality will fail.
::1     localhost.localdomain   localhost

Experimenting reveals that if both lines are present, adding or deleting a
network interface with system-config-network results in the first line being
deleted.  If only one line is present (it doesn't matter which one), it's left
alone.

In light of the last comment from Andre, I do recall adding port 10000/tcp
as a trusted port during install time, i.e., before first boot from the HDD.
This was in anticipation of installing webmin.

Echoing the findings of comment #10. I know of a few others who have been bitten
(mildly) by this too. I think this should be re-assigned from anaconda to
system-config-network.

OK, this bug is fixed in anaconda.  I am writing out correct lines for localhost
and localhost6.  But if you run system-config-network, that's different code. 
It should preserve those entries, so this really isn't much of a problem.  But
I'll file a bug against that component to make sure they add code to write out
localhost6 if they need to.

Unfortunately, this bug is present in FC6.  Sorry.

*** Bug 212815 has been marked as a duplicate of this bug. ***

*** Bug 216919 has been marked as a duplicate of this bug. ***

Please also look at 214932.

My symptom is described in 216919.

This may well be an Anaconda bug but no update can fix an Anaconda bug (as I
understand it).  To get a fix in out there for FC6, s-c-n needs to have a
work-around for the Anaconda bug.

*** Bug 223428 has been marked as a duplicate of this bug. ***

*** Bug 209597 has been marked as a duplicate of this bug. ***