Re: donegal fell into hyperspace and can't get up

[turnbull@example.com (Stephen J. Turnbull)]

>>>>> Dennis McMurchy <denismcm@example.com> writes:

    Dennis>   Thankyou so much, Jim and Steve.  My problem with
    Dennis> sendmail is now solved.  You emboldened me to try doing
    Dennis> exactly what it says NOT to do in the header of
    Dennis> /etc/hosts.  I can't specify an IP address for my hostname
    Dennis> because I'm only on the net when I dial up my provider,
    Dennis> who allocates addresses dynamically, so I just added the
    Dennis> line 

    Dennis> 127.0.0.1 donegal

    Dennis>   By God, it did the trick - sendmail doesn't complain,
    Dennis> and actually moves the mail.

    Dennis>   This is my /etc/hosts :

    Dennis> 127.0.0.1	localhost
    Dennis> 127.0.0.1	donegal

I'm not sure this is entirely correct; maybe it should be done as an
alias:

127.0.0.1	donegal	localhost

    Dennis> # End of hosts.

    Dennis>   I'm a little nervous about problems that this might
    Dennis> cause further down the road, but it sure works.  The thing
    Dennis> is though, as Steve said, sendmail ought to be able to
    Dennis> figure out that donegal is localhost.  Things certainly
    Dennis> were not this way in my earlier Slackware installation,
    Dennis> and should not be this way now.  If anyone can figure out
    Dennis> a more elegant solution that would allow me to remove this
    Dennis> line from /etc/hosts, I'd feel better about it.

I don't understand exactly how these things work since I haven't
looked at the source code.  However, what you should be able to do is
change /etc/hosts.conf to "bind, hosts" and run named(8).  Then
/etc/hosts should not be consulted when your inet connection is up,
because named should be asking your provider's nameserver.

You should be able to configure named to alias donegal to the IP
address assigned by your provider.  (But the man page is not exactly
crystal clear....)

[Theoretically, by having multiple named.boot files and using

cd /etc
cp -f named.boot.now-needed named.boot
kill SIGHUP `cat /etc/named.pid`"

you should be able to reconfigure it on the fly if necessary.  I don't 
think it should be necessary.]

Elegant?  Dunno....

    Dennis>   Great to be running again though.  Thanks again, guys.

De nada.

>>>>> "Jim" == Jim Tittsler <jwt@example.com> writes:

    Jim> In article <Pine.LNX.3.91.960912131213.421B-100000@example.com>,
    Jim> you wrote:
    >> NOT to do in the header of /etc/hosts.  I can't specify an IP
    >> address for my hostname because I'm only on the net when I dial
    >> up my provider, who allocates addresses dynamically, so I just

    Jim> You can add one.  Just pick one from the blocks of
    Jim> "disconnected networks" like 172.16.xx.xx.  When you get a

They don't necessarily stay disconnected....  Shouldn't be a problem,
but weird things happen occasionally.

    Jim> dynamically assigned IP address during the connection it will
    Jim> be added to the routing tables (and your machine will become
    Jim> something like fukuoka37.junk.or.jp in addition to donegal :-).

You should be able to delete the junk address from the routing tables, 
but I forget exactly how.  You want to do this just before you
connect, I think.

-- 
                           Stephen John Turnbull
University of Tsukuba                                        Yaseppochi-Gumi
Institute of Policy and Planning Sciences  http://turnbull.sk.tsukuba.ac.jp/
Tennodai 1-1-1, Tsukuba, 305 JAPAN                 turnbull@example.com
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