Brian wrote: > Bob Proulx wrote: > > Brian wrote: > > > True. What do think about the lack of '127.0.1.1 localhost' in
It is the "127.0.1.1 localhost" to which I was disagreeing. That would be unusual. It is still the loopback device so off the top of my head I think everything should still work okay. But for best compatibilty I think 127.0.0.1 should always be localhost the reverse. If the actual hostname of the system is "localhost" then there is no need for any other entry other than the 127.0.0.1 entry and the 127.0.1.1 entry isn't needed at all. (Now I need to verify that the installer doesn't add it in that case. I recall that it does not.) > > > etc/hosts? Squeeze and Wheezy installs would both put this line in. > > > > Process check! I think you have mixed up the two cases. Since a long > > time now Debian installs a /etc/hosts file that will look like this: > > > > 127.0.0.1 localhost > > Agreed. > > > 127.0.1.1 foo.example.com foo > > Agreed - sort of :). > > A line in /etc/hosts has the form > > IP_address canonical_hostname [aliases...] > > aliases are optional and the second field will always be the canonical > hostname. So far so good! :-) > What a Debian install puts for 127.0.1.1 depends on how the install took > place. If the user just uses 'install' d-i can get /etc/hostname and the > domain name from whatever dhcp server is being used. Hmm... I hadn't thought about an odd DHCP configuration creating something unusual there. I am still suspicious... I think it works the same regardless. > 127.0.1.1 foo.example.com foo > > is what the user could get. Since I usually install things in what I consider a "normal" state I completely agree. That is what you would get. Now that you mentioned the case of what happens if DHCP returns something unusual I think I would need to check. But I think it still behaves the same regardless. I don't think anything the DHCP server returns is going to affect this. But I can't say for certain without looking and testing. It might. I am more interested now in what happens in a CD#1 install completely offline. > Suppose the server doesn't provide a domain name. Then she will have > > 127.0.1.1 foo > > because there is no need for an alias. That is a good question! But doesn't the installer ask you for a domain name specifically? I believe it does. Therefore the user should always enter a domain name. But if they don't then I don't know what the installer puts there by default. I _thought_ the installer put the special "localdomain" string there in the case that the user left it empty. Because sometimes there isn't any reasonable thing to put there. In that case it creates a consistent and valid configuration using localhost and localdomain. That way applications that require a domain name to be present will have a constructed one that will work even if bogus. (As I recall this predates RFC 2606 which created a .localhost domain.) The idea is that some applications such as Postfix for one example, along with others, that really want a fully qualified hostname can have a fully consistent configuration by using localhost.localdomain. The localdomain part is a created construct. But on an unconnected system everything can map consistently and everything can work regardless. > For an expert install the hostname and domain name can be specified, so > either > > 127.0.1.1 foo.example.com foo > > or, if the domain name is left blank, > > 127.0.1.1 foo > > would be seen. Doesn't it create an entry like this? I will need to test it in order to see what it creates in that case. 127.0.1.1 foo.localdomain foo I will try it later and report back. :-) > With preseeding the hostname can be be preseeded but not the domain > name. So I'd expect both the previous two variants to be possible. The domain *can* be preseeded. I do that all of the time. Really! On the install command line. For me usually through the PXE network boot syslinux interface. hostname=junk domain=proulx.com > I do not think we are in serious disagreement. Sometimes we disagree but it is never serious. I always look forward to your postings Brian. They are always high quality helpful postings. I enjoy our discussions. Bob
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