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Too many system names

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  Too many system names Gary Roach <gary719_list1@verizon.net> - 2015-08-25 21:40 +0200
    Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-25 23:20 +0200
      Re: Too many system names David Wright <deblis@lionunicorn.co.uk> - 2015-08-27 21:30 +0200
        Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-27 22:30 +0200
          Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-27 22:40 +0200
            Re: Too many system names Gary Roach <gary719_list1@verizon.net> - 2015-08-28 01:10 +0200
              Re: Too many system names Jörg-Volker Peetz <jvpeetz@web.de> - 2015-08-28 15:30 +0200
                Re: Too many system names Gary Roach <gary719_list1@verizon.net> - 2015-08-28 16:50 +0200
                  Re: Too many system names Jörg-Volker Peetz <jvpeetz@web.de> - 2015-08-28 17:50 +0200
                  Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-28 23:20 +0200
              Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-30 22:30 +0200
                Re: Too many system names Jochen Spieker <ml@well-adjusted.de> - 2015-08-30 22:30 +0200
          Re: Too many system names David Wright <deblis@lionunicorn.co.uk> - 2015-08-30 06:40 +0200

#156793 — Too many system names

I've been fighting a redmine installation on my jessie system for a 
couple of weeks but have finally got it working with one minor flaw. The 
program will only start if I use my FQDN supercrunch.quantum. Now this 
is not a big problem in itself. But..., I am afraid that if I don't 
clean up a few things that this is going to bite me in my nether regions 
later.

The problem is that apache2 can't find the server name I have used and 
is resorting to the dns in my router. The name of my computer in the 
router is supercrunch.quantum. (I had to call it something) .

In the /etc/apache2/sites-enabled/000-default.conf
	ServerName 127.0.0.1


In the /etc/apache2/sites-enabled/apache2-passenger-alias.conf
	ServerName is Commented out

In the /etc/apache2/sites-enabled/redmine.conf
	ServerName is commented out

The 127.0.0.1 in the default.conf file seems to be the problem but I am 
not sure of the nature of the problem. I always get thrown for a loop 
when asked for things like server names and application names. May be 
i'm a little dense but I find the terms confusing.

Apache obviously doesn't much care for the localhost IP. So what should 
I be using.

Thanks for all help past, present and future.

Gary R.

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#156796

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Gary Roach:
> I've been fighting a redmine installation on my jessie system for a couple
> of weeks but have finally got it working with one minor flaw. The program
> will only start if I use my FQDN supercrunch.quantum.

How do you "start" redmine? By opening it in a browser? What happens
when you do that?

> The problem is that apache2 can't find the server name I have used and is
> resorting to the dns in my router. The name of my computer in the router is
> supercrunch.quantum. (I had to call it something) .

Where's the problem in Apache using your router's DNS? Is it just that
the router doesn't resolve unqualified names (supercrunch without the
domain)?

> In the /etc/apache2/sites-enabled/000-default.conf
> 	ServerName 127.0.0.1

Using an IP address as ServerName is odd. You have to use the hostname
that you want to use in URLs here. If you want to call
http://supercrunch.quantum/ you should set "ServerName
supercrunch.quantum". You can also set a "ServerAlias supercrunch" when
you get your DNS issues sorted out.

> The 127.0.0.1 in the default.conf file seems to be the problem but I am not
> sure of the nature of the problem.

Me neither, because you described it insufficiently. :)

> I always get thrown for a loop when asked
> for things like server names and application names. May be i'm a little
> dense but I find the terms confusing.

A hostname is just the name for a host. (Almost) anything will do. A
fully qualified domain name (FQDN) is a hostname with a domain name at
the end. This is actually the same as in all other URLs that you stumble
upon, even though big sites hide many machines behind one simple name
(like google.com).

You can register an official domain name using any of the numerous
registrars for the various TLDs (like .com or .us). That might sound a
little overengineered for a small home LAN but it only costs a few
dollars a year, mostly depending on the TLD you want to use. If you
register example.com, you can invent any name you like, e.g.
router.home.example.com and flurry.example.com. But you should find out
beforehand whether you can configure your router to hand out this domain
name to DHCP clients (or use fixed network settings which mostly
sucks).

J.
-- 
I eat meat and am concerned about bugs which are resistant to
antibiotics.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#156915

Quoting Jochen Spieker (ml@well-adjusted.de):
> Gary Roach:
> > I've been fighting a redmine installation on my jessie system for a couple
> > of weeks but have finally got it working with one minor flaw. The program
> > will only start if I use my FQDN supercrunch.quantum.
> 
> How do you "start" redmine? By opening it in a browser? What happens
> when you do that?
> 
> > The problem is that apache2 can't find the server name I have used and is
> > resorting to the dns in my router. The name of my computer in the router is
> > supercrunch.quantum. (I had to call it something) .
> 
> Where's the problem in Apache using your router's DNS? Is it just that
> the router doesn't resolve unqualified names (supercrunch without the
> domain)?

I didn't know bog-standard domestic routers ran a DNS server. I
thought they just asked the external nameservers, either set up
automatically from the ISP or manually configured if using public ones.

> > In the /etc/apache2/sites-enabled/000-default.conf
> > 	ServerName 127.0.0.1
> 
> Using an IP address as ServerName is odd. You have to use the hostname
> that you want to use in URLs here.

The latter seems odd, seeing as the first thing you would normally do
with a hostname is look it up and turn it into an IP address.

> If you want to call
> http://supercrunch.quantum/ you should set "ServerName
> supercrunch.quantum". You can also set a "ServerAlias supercrunch" when
> you get your DNS issues sorted out.
> 
> > The 127.0.0.1 in the default.conf file seems to be the problem but I am not
> > sure of the nature of the problem.
> 
> Me neither, because you described it insufficiently. :)
> 
> > I always get thrown for a loop when asked
> > for things like server names and application names. May be i'm a little
> > dense but I find the terms confusing.

I don't know how you have your LAN configured. I use DHCP from the
router, which assigns fixed IP#s by MAC address. That way, I can
list my own hosts in /etc/hosts and avoid needing a DNS server to
resolve their names:

127.0.0.1       localhost
127.0.1.1       thishost
192.168.1.1     router
192.168.1.11    otherhosta
192.168.1.12    otherhostb
192.168.1.31    HP0C00E0    hp8000

> A hostname is just the name for a host. (Almost) anything will do. A
> fully qualified domain name (FQDN) is a hostname with a domain name at
> the end. This is actually the same as in all other URLs that you stumble
> upon, even though big sites hide many machines behind one simple name
> (like google.com).
> 
> You can register an official domain name using any of the numerous
> registrars for the various TLDs (like .com or .us). That might sound a
> little overengineered for a small home LAN but it only costs a few
> dollars a year, mostly depending on the TLD you want to use.

Agreed: overengineered.

> If you
> register example.com, you can invent any name you like, e.g.
> router.home.example.com and flurry.example.com. But you should find out
> beforehand whether you can configure your router to hand out this domain
> name to DHCP clients (or use fixed network settings which mostly
> sucks).

I don't set any domainname. The only consequence I know of is exim
complaining at boot:

Starting MTA:hostname --fqdn did not return a fully qualified name, dc_minimaldns will not work.
Please fix your /etc/hosts setup.

Were I on dialup, I might be able to see whether this has any knock-on
effect. As it is, everything just works (and exim delivers local mail/
feeds a smarthost). If it doesn't (for that reason) I shall file a bug.
BTW Bug #685045 reports the symptom, but has never been responded to.

Cheers,
David.

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#156921

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David Wright:
> Quoting Jochen Spieker (ml@well-adjusted.de):
>> 
>> Where's the problem in Apache using your router's DNS? Is it just that
>> the router doesn't resolve unqualified names (supercrunch without the
>> domain)?
> 
> I didn't know bog-standard domestic routers ran a DNS server.

I think all of them do. They have simple caching-only DNS servers that
just ask your ISP's DNS resolver for all but local hostnames.

Your computers should request an IP address and at the same time
register what they think is their local hostname on the router (all via
DHCP). This way your router's DNS server should be able to resolve local
hostnames for other clients, rendering your editing of hosts files
unnecessary.

Usually your router also tells the DHCP clients the name of the network
they are in. My AVM Fritzbox (German manufacturer) hands out
".fritz.box" which I find so horrible that I run a separate DNS/DHCP
server (dnsmasq) on another box.

> I thought they just asked the external nameservers, either set up
> automatically from the ISP or manually configured if using public ones.

That plus resolution of local hostnames.

>> Using an IP address as ServerName is odd. You have to use the hostname
>> that you want to use in URLs here.
>
> The latter seems odd, seeing as the first thing you would normally do
> with a hostname is look it up and turn it into an IP address.

Yes, but most people are better at remembering names than IP addresses
and the lookup is performed automatically whenever you use it.

How often do you open http://173.194.116.166 in order to go to Google?
Or, god forbid, http://[2a00:1450:4001:80e::1009] (in case you already
have IPv6)?

> I don't know how you have your LAN configured. I use DHCP from the
> router, which assigns fixed IP#s by MAC address. That way, I can
> list my own hosts in /etc/hosts and avoid needing a DNS server to
> resolve their names:
> 
> 127.0.0.1       localhost
> 127.0.1.1       thishost
> 192.168.1.1     router
> 192.168.1.11    otherhosta
> 192.168.1.12    otherhostb
> 192.168.1.31    HP0C00E0    hp8000

… and you have to keep that file in sync on all hosts. I use DHCP as
well and make sure my clients send their hostname when requesting an IP
address vie DHCP. Debian does this automatically. Then all clients in
the local network can resolve their names just fine and I don't need to
edit hosts files.

I do use fixed IPs for a few hosts as well, but mostly because I use
port forwardings or local services that I want to bind to a specific
address. But this is just a configuration on the DHCP server and nothing
I have to repeat on all boxes in my network.

If this sounds as if I had an awful lot of computers: no, I don't think
so. It's just an awful lot of, well, _devices_ with wired/wireless
networking capability:

- two laptops (one for me, one for my wife)
- one desktop (seldomly used)
- one file/print/mail/whatever server in the basement
- two Android phones
- one iPad (1st gen, essentially a doorstop)
- one Roku Soundbridge, a hardware streaming client hooked up to my hifi
  system
- one network printer
- one ChromeCast
- one Raspberry Pi 2
- one manageable switch
- one not-so-smart TV

Not all of those need to talk with each other but I find it is easiest
if everything is managed the same way.  DNS coupled with DHCP works fine
for that. If one of your machines provides a service for all of the
others (like sending mail through your mail provider's relay), you may
even want to set up alias hostnames (like "mail"). This enables you to
easily move this service to another host later on without changing all
of your clients. :)

Yes, I may be guilty of overengineering a few things. But I now spend
considerably less time with this than a few years ago and I think this
is related to the way I have set things up.

> I don't set any domainname. The only consequence I know of is exim
> complaining at boot:
> 
> Starting MTA:hostname --fqdn did not return a fully qualified name, dc_minimaldns will not work.
> Please fix your /etc/hosts setup.

Well, Exim is written primarily as a "real" mail server (MTA). Your
usage is supported (and common), but the authors just expect a "proper"
environment. A network without a name (not even a fake name) isn't.

Anyway, sorry that I am not really helping you with your redmine issue.
If it persists it might help if you summarized what exactly you want to
achieve ("I want to enter http://whatever into my browser and see
redmine's login dialog"), how you try to do that ("here's my config
again in case you forgot") and what actually happens ("when I open the
address in my browser, I get this exact error message and see the
following in my Apache logs").

Regards,
J.
-- 
Fashion is more important to me than war, famine, disease or art.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#156922

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Jochen Spieker:
> David Wright:
>> Quoting Jochen Spieker (ml@well-adjusted.de):
>> 
>>> Using an IP address as ServerName is odd. You have to use the hostname
>>> that you want to use in URLs here.
>> 
>> The latter seems odd, seeing as the first thing you would normally do
>> with a hostname is look it up and turn it into an IP address.
> 
> Yes, but most people are better at remembering names than IP addresses
> and the lookup is performed automatically whenever you use it.

BTW, the real reason that ServerName is usually a hostname instead of an
IP address is that with HTTP/1.1 you can host multiple domains using
only one IP address. Browsers not only resolve the hostname to an IP
address and connect to that, they also tell the webserver which hostname
they want to talk to and the webserver can serve different content
depending on that hostname.

Apache calls that "name-based virtual hosting":
http://httpd.apache.org/docs/2.4/vhosts/name-based.html

J.
-- 
Every day in every way I am getting better and better.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#156926

On 08/27/2015 01:33 PM, Jochen Spieker wrote:
> Jochen Spieker:
>> David Wright:
>>> Quoting Jochen Spieker (ml@well-adjusted.de):
>>>
>>>> Using an IP address as ServerName is odd. You have to use the hostname
>>>> that you want to use in URLs here.
>>> The latter seems odd, seeing as the first thing you would normally do
>>> with a hostname is look it up and turn it into an IP address.
>> Yes, but most people are better at remembering names than IP addresses
>> and the lookup is performed automatically whenever you use it.
> BTW, the real reason that ServerName is usually a hostname instead of an
> IP address is that with HTTP/1.1 you can host multiple domains using
> only one IP address. Browsers not only resolve the hostname to an IP
> address and connect to that, they also tell the webserver which hostname
> they want to talk to and the webserver can serve different content
> depending on that hostname.
>
> Apache calls that "name-based virtual hosting":
> http://httpd.apache.org/docs/2.4/vhosts/name-based.html
>
> J.
OK: With ServerName set to supercrunch and doing a systemctl reload and 
then  systemctl -l status, I get the following message (In part)

Aug 25 23:41:53 supercrunch apache2[662]: Starting web server: 
apache2AH00557: apache2: apr_sockaddr_info_get() failed for supercrunch
Aug 25 23:41:53 supercrunch apache2[662]: AH00558: apache2: Could not 
reliably determine the server's fully qualified domain name, using 
127.0.0.1. Set the 'ServerName' directive globally to suppress this message

With this set up, I tried to run supercrunch/redmine, localhost/redmine, 
127.0.0.1/redmine. None worked.

I change the ServerName to 127.0.0.1 in the 000-default.conf file with 
the following result.

Aug 25 23:41:53 supercrunch apache2[662]: Starting web server: 
apache2AH00557: apache2: apr_sockaddr_info_get() failed for supercrunch
Aug 25 23:41:53 supercrunch apache2[662]: AH00558: apache2: Could not 
reliably determine the server's fully qualified domain name, using 
127.0.0.1. Set the 'ServerName' directive globally to suppress this message

Same result as before. The 404 web page  returned is interesting in that 
it says:

Not Found

The requested URL /redmine was not found on this server.
Apache/2.4.10 (Debian) Server at supercrunch Port 80

I'm wondering why the server can't fine redmine.  The redmine.conf is in 
the sites-enabled directory with a softlink to the sites-available 
directory.

Additional info:
/etc/hosts/  file

127.0.0.1       localhost

# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

/etc/network/interfaces file

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug eth0
iface eth0 inet dhcp
         hostname supercrunch


I am using  dhcp for my internal network but set some of my systems to 
hard 192.168.1.0/24 addresses. This simplifies things when mucking 
around with things like this problem. Most of my stuff is straight dhcp.

I don't know whether any of this helps. I do appreciate all of your help.

Gary R.

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#156963

Gary Roach wrote on 08/28/2015 01:01:
<snip>
> 
> The requested URL /redmine was not found on this server.
> Apache/2.4.10 (Debian) Server at supercrunch Port 80
> 
> I'm wondering why the server can't fine redmine.  The redmine.conf is in the
> sites-enabled directory with a softlink to the sites-available directory.
> 
<snip>

How does your redmine.conf file look like?

Did you make any changes in /usr/share/redmine/config for using redmine via the
sub-URI /redmine?
Especially, in /usr/share/redmine/config/environments.rb?

Regards,
jvp.

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#156974

On 08/28/2015 06:24 AM, Jörg-Volker Peetz wrote:
> Gary Roach wrote on 08/28/2015 01:01:
> <snip>
>> The requested URL /redmine was not found on this server.
>> Apache/2.4.10 (Debian) Server at supercrunch Port 80
>>
>> I'm wondering why the server can't fine redmine.  The redmine.conf is in the
>> sites-enabled directory with a softlink to the sites-available directory.
>>
> <snip>
>
> How does your redmine.conf file look like?

The following is in /etc/apache2/sites-enabled/redmine.conf

# The passenger module (from the libapache2-mod-passenger package) must be
# enabled
<VirtualHost *:80>
     # ServerName localhost
     # this is the passenger config
     RailsEnv production
     SetEnv X_DEBIAN_SITEID "default"
     PassengerDefaultUser www-data
     Alias "/plugin_assets/" /var/cache/redmine/default/plugin_assets/
     DocumentRoot /usr/share/redmine/public
     <Directory "/usr/share/redmine/public">
         Allow from all
         Options -MultiViews
         Require all granted
     </Directory>
</VirtualHost>

>
> Did you make any changes in /usr/share/redmine/config for using redmine via the
> sub-URI /redmine?
> Especially, in /usr/share/redmine/config/environments.rb?
I have made no changes to either of these files. While looking through 
the files, I did notice that there didn't seem to be any html files 
(except 2 error files) in any of the redmine paths. ????
>
> Regards,
> jvp.
>
>
>
Thank you for your help

Gary R.

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#156983

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Gary Roach wrote on 08/28/2015 16:48:
> On 08/28/2015 06:24 AM, Jörg-Volker Peetz wrote:
>> Gary Roach wrote on 08/28/2015 01:01:
>> <snip>
>>> The requested URL /redmine was not found on this server.
>>> Apache/2.4.10 (Debian) Server at supercrunch Port 80
>>>
>>> I'm wondering why the server can't fine redmine.  The redmine.conf is in the
>>> sites-enabled directory with a softlink to the sites-available directory.
>>>
>> <snip>
>>
>> How does your redmine.conf file look like?
> 
> The following is in /etc/apache2/sites-enabled/redmine.conf
> 
> # The passenger module (from the libapache2-mod-passenger package) must be
> # enabled
> <VirtualHost *:80>
>     # ServerName localhost
>     # this is the passenger config
>     RailsEnv production
>     SetEnv X_DEBIAN_SITEID "default"
>     PassengerDefaultUser www-data
>     Alias "/plugin_assets/" /var/cache/redmine/default/plugin_assets/
>     DocumentRoot /usr/share/redmine/public
>     <Directory "/usr/share/redmine/public">
>         Allow from all
>         Options -MultiViews
>         Require all granted
>     </Directory>
> </VirtualHost>
> 
>>
>> Did you make any changes in /usr/share/redmine/config for using redmine via the
>> sub-URI /redmine?
>> Especially, in /usr/share/redmine/config/environments.rb?
> I have made no changes to either of these files. While looking through the
> files, I did notice that there didn't seem to be any html files (except 2 error
> files) in any of the redmine paths. ????

There are none also in my nginx/unicorn configuration.
I'm not sure which redmine version you're now using.

For using the sub-URI /redmine I'd expect to see "Alias"es as in
/usr/share/doc/redmine/examples/apache2-passenger-alias.conf which start with
"/redmine"?

I, with redmine 3, do set the environment variable RAILS_RELATIVE_URL_ROOT to
"/redmine" and I had to install a soft link from
/usr/share/redmine/public/redmine -> . (done by something like "cd
/usr/share/redmine/public ; ln -s . redmine").
Further I had to change the file environment.rb in /usr/share/redmine/config .
But I'm not sure if that works in your case. Anyhow, I'll attach the file.

Regards,
jvp.

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#157000

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Gary Roach:
> On 08/28/2015 06:24 AM, Jörg-Volker Peetz wrote:
>> 
>> How does your redmine.conf file look like?
> 
> The following is in /etc/apache2/sites-enabled/redmine.conf
> 
> # The passenger module (from the libapache2-mod-passenger package) must be
> # enabled
> <VirtualHost *:80>
>     # ServerName localhost
>     # this is the passenger config

If you don't set a ServerName, how should Apache know for which requests
this VirtualHost is responsible?

My advice is always to use a specific CustomLog and ErrorLog for each
VirtualHost. Otherwise you cannot tell whether Apache actually uses the
VirtualHost that you want it to use.

J.
-- 
If I could travel in time I would show my minidisc to the Romans and
become Caesar until the batteries ran out.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#157143

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Gary Roach:
>
> OK: With ServerName set to supercrunch and doing a systemctl reload and then
> systemctl -l status, I get the following message (In part)
> 
> Aug 25 23:41:53 supercrunch apache2[662]: Starting web server:
> apache2AH00557: apache2: apr_sockaddr_info_get() failed for supercrunch

That may be related to a line like 'Listen supercrunch:80" or maybe
"<VirtualHost supercrunch:80>". If your system cannot resolve that name,
Apache doesn't know what to do with it.

Please note that a "ServerName supercrunch" should not lead to that
problem since in this case "supercrunch" is just a string that Apache
expects in the Host header of requests. Technically, I don't think it
has to be a valid DNS name on the server.

> With this set up, I tried to run supercrunch/redmine, localhost/redmine,
> 127.0.0.1/redmine. None worked.

Please, describe what "None worked" exactly means and what you find in
the VirtualHost-specific log files I proposed to set up

J.
-- 
I'm being paid to act weirdly.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#157145

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Sorry, please ignore this post. I didn't notice I was replying to an
older response.

Regards,
Jochen.

Jochen Spieker:
> Gary Roach:
>> 
>> OK: With ServerName set to supercrunch and doing a systemctl reload and then
>> systemctl -l status, I get the following message (In part)
>> 
>> Aug 25 23:41:53 supercrunch apache2[662]: Starting web server:
>> apache2AH00557: apache2: apr_sockaddr_info_get() failed for supercrunch
> 
> That may be related to a line like 'Listen supercrunch:80" or maybe
> "<VirtualHost supercrunch:80>". If your system cannot resolve that name,
> Apache doesn't know what to do with it.
> 
> Please note that a "ServerName supercrunch" should not lead to that
> problem since in this case "supercrunch" is just a string that Apache
> expects in the Host header of requests. Technically, I don't think it
> has to be a valid DNS name on the server.
> 
>> With this set up, I tried to run supercrunch/redmine, localhost/redmine,
>> 127.0.0.1/redmine. None worked.
> 
> Please, describe what "None worked" exactly means and what you find in
> the VirtualHost-specific log files I proposed to set up
> 
> J.
> -- 
> I'm being paid to act weirdly.
> [Agree]   [Disagree]
>                  <http://www.slowlydownward.com/NODATA/data_enter2.html>



-- 
If I was a supermodel I would give all my cocaine to the socially
excluded.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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#157098

Quoting Jochen Spieker (ml@well-adjusted.de):
> David Wright:
> > Quoting Jochen Spieker (ml@well-adjusted.de):
> >> 
> >> Where's the problem in Apache using your router's DNS? Is it just that
> >> the router doesn't resolve unqualified names (supercrunch without the
> >> domain)?
> > 
> > I didn't know bog-standard domestic routers ran a DNS server.
> 
> I think all of them do. They have simple caching-only DNS servers that
> just ask your ISP's DNS resolver for all but local hostnames.
> 
> Your computers should request an IP address and at the same time
> register what they think is their local hostname on the router (all via
> DHCP).

Yes, all that happens. I have the same hostname written in three
places:
1) the router, which has a list of IP#s/device names/MAC addresses
   in order that it always issues the same IP# for a given device
   via (DHCP),
2) /etc/hosts: 127.0.1.1 here or 192.168.1.N elsewhere,
3) wicd configuration.

> This way your router's DNS server should be able to resolve local
> hostnames for other clients, rendering your editing of hosts files
> unnecessary.

Yes, but a bog-standard one doesn't appear to have even a simple
caching-only DNS server, only a DHCP one.

> Usually your router also tells the DHCP clients the name of the network
> they are in. My AVM Fritzbox (German manufacturer) hands out
> ".fritz.box" which I find so horrible that I run a separate DNS/DHCP
> server (dnsmasq) on another box.

At some time IIRC Debian put   localnet 192.168.1.0   into
/etc/networks but I'm not sure if that's still true. Hosts that have
that line may be cruft-laden as a result of being upgraded over several
distributions (squeeze is now my earliest dist origin.)

> > I thought they just asked the external nameservers, either set up
> > automatically from the ISP or manually configured if using public ones.
> 
> That plus resolution of local hostnames.

... if they themselves run a nameserver.

> >> Using an IP address as ServerName is odd. You have to use the hostname
> >> that you want to use in URLs here.
> >
> > The latter seems odd, seeing as the first thing you would normally do
> > with a hostname is look it up and turn it into an IP address.
> 
> Yes, but most people are better at remembering names than IP addresses
> and the lookup is performed automatically whenever you use it.

(Tell me about it! That's why I've always argued that the Grub scripts
ought to treat LABELs on a par with UUIDs as they're much easier for
humans to handle.)

> How often do you open http://173.194.116.166 in order to go to Google?
> Or, god forbid, http://[2a00:1450:4001:80e::1009] (in case you already
> have IPv6)?

Never, for google etc. That was not my point, which was that the first
thing *computers* do is look up the IP#. I think you'd be surprised if
your browser *couldn't* handle, say, http://173.194.115.80/ but *could*
handle http://www.google.com/.

(However, my computers all have
Acquire::http::Proxy "http://192.168.1.19:3142/";
in /etc/apt/apt.conf because at installation time they have no
way of looking up that computer's hostname.)

So why would 127.0.0.1 be any odder than localhost? My browsers are
quite happy with any of
http://localhost:3142/acng-report.html
http://127.0.0.1:3142/acng-report.html
http://192.168.1.19:3142/acng-report.html
http://alum:3142/acng-report.html
http://127.0.1.1:3142/acng-report.html

> > I don't know how you have your LAN configured. I use DHCP from the
> > router, which assigns fixed IP#s by MAC address. That way, I can
> > list my own hosts in /etc/hosts and avoid needing a DNS server to
> > resolve their names:
> > 
> > 127.0.0.1       localhost
> > 127.0.1.1       thishost
> > 192.168.1.1     router
> > 192.168.1.11    otherhosta
> > 192.168.1.12    otherhostb
> > 192.168.1.31    HP0C00E0    hp8000
> 
> … and you have to keep that file in sync on all hosts. I use DHCP as
> well and make sure my clients send their hostname when requesting an IP
> address vie DHCP. Debian does this automatically. Then all clients in
> the local network can resolve their names just fine and I don't need to
> edit hosts files.

Obviously you have something which many people don't have. So
I can't do it that way.

> I do use fixed IPs for a few hosts as well, but mostly because I use
> port forwardings or local services that I want to bind to a specific
> address. But this is just a configuration on the DHCP server and nothing
> I have to repeat on all boxes in my network.

All my hosts (and the TVs/Roku boxes/printers.mobiles) have fixed IP#s
set by the router as at (1) above.

> If this sounds as if I had an awful lot of computers: no, I don't think
> so. It's just an awful lot of, well, _devices_ with wired/wireless
> networking capability:

Yes, likewise. 14 MAC addresses in the router, a slightly different mix.

[...]

> Yes, I may be guilty of overengineering a few things. But I now spend
> considerably less time with this than a few years ago and I think this
> is related to the way I have set things up.

I use scripts to configure my Debian systems so it's quick.

> > I don't set any domainname. The only consequence I know of is exim
> > complaining at boot:
> > 
> > Starting MTA:hostname --fqdn did not return a fully qualified name, dc_minimaldns will not work.
> > Please fix your /etc/hosts setup.
> 
> Well, Exim is written primarily as a "real" mail server (MTA). Your
> usage is supported (and common), but the authors just expect a "proper"
> environment. A network without a name (not even a fake name) isn't.

Exim was written by a guy who hacked code to suit the environment in
which it found itself. Single-user machines are just one mode of use,
and one that the author had to come to grips with (in terms of support
and documentation) when it became popular on linux, particularly Debian.

> Anyway, sorry that I am not really helping you with your redmine issue.

I'm not the one with the issue. I'm more interested in software that
apparently relies on the resolving of dotless hostnames by DNS (rather
than files) and objects to the IP# in place of the hostname.

Cheers,
David.

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