All we're doing is copying the system /etc/hosts into the chroot when the chroot is created. Not sure I want to take on editing of that file to see if it contains an IPv6 entry and add it if it doesn't.

(In reply to comment #1)
> All we're doing is copying the system /etc/hosts into the chroot when the
> chroot is created. Not sure I want to take on editing of that file to see if it
> contains an IPv6 entry and add it if it doesn't.  

That's not exactly true.
If you switch this feature off, default /etc/hosts is written to the chroot:

if not config_opts['use_host_resolv'] and not config_opts['files'].has_key('etc/hosts'):
    config_opts['files']['etc/hosts'] = "127.0.0.1 localhost localhost.localdomain %s\n" % gethostname();

Ah, good point.

So what you'd like is a sane default if not copying the system hosts file?

Exactly.
Since this is how koji uses mock by default, it would be nice to fix it.

That makes sense. 

One question: do we need to add the results of gethostname() to the IPv6 line, or can we just use the line you listed above? I mean do we need to do this:

    # default /etc/hosts contents
    if not config_opts['use_host_resolv'] and not  
        config_opts['files'].has_key('etc/hosts'):
        config_opts['files']['etc/hosts'] = '''
127.0.0.1 localhost localhost.localdomain %s
::1       localhost localhost.localdomain localhost6 localhost6.localdomain6 %s
''' % (gethostname(), gethostname())

or do we do this:

    # default /etc/hosts contents
    if not config_opts['use_host_resolv'] and not  
        config_opts['files'].has_key('etc/hosts'):
        config_opts['files']['etc/hosts'] = '''
127.0.0.1 localhost localhost.localdomain %s
::1       localhost localhost.localdomain localhost6 localhost6.localdomain6
''' % gethostname()

mock-1.0.2-1.el5 has been submitted as an update for Fedora EPEL 5.
http://admin.fedoraproject.org/updates/mock-1.0.2-1.el5

mock-1.0.2-1.el5 has been pushed to the Fedora EPEL 5 testing repository.  If problems still persist, please make note of it in this bug report.
 If you want to test the update, you can install it with 
 su -c 'yum --enablerepo=updates-testing update mock'.  You can provide feedback for this update here: http://admin.fedoraproject.org/updates/EL-5/FEDORA-EPEL-2009-1055

mock-1.0.2-1.fc11 has been pushed to the Fedora 11 testing repository.  If problems still persist, please make note of it in this bug report.
 If you want to test the update, you can install it with 
 su -c 'yum --enablerepo=updates-testing update mock'.  You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F11/FEDORA-2009-13597

(In reply to comment #5)
> One question: do we need to add the results of gethostname() to the IPv6 line,
> or can we just use the line you listed above? I mean do we need to do this:

I didn't answer, because both variants from comment #5 looks good to me.

However what you have done afterwards is none of the variants above, or am I wrong?

The hostname in /etc/hosts is not needed by curl, which is actually the reason of this bug opened, but I am only afraid that removing hostname completely might break something else.

mock-1.0.2-1.fc11 has been pushed to the Fedora 11 stable repository.  If problems still persist, please make note of it in this bug report.

mock-1.0.2-1.el5 has been pushed to the Fedora EPEL 5 stable repository.  If problems still persist, please make note of it in this bug report.

(In reply to comment #9)
> The hostname in /etc/hosts is not needed by curl, which is actually the reason
> of this bug opened, but I am only afraid that removing hostname completely
> might break something else.    

Mock buildroots are isolated environment and processes inside are not supposed to communicate over network. They also shouldn't need even the hostname (localhost should be sufficient). I'm OK with the change, we'll see what happens...