"No DNS server configuration found" when approving spam reports

"No DNS server configuration found" when approving spam reports

[Steinar Bang]

Platform: Intel Core 2 Duo CPU,
	  Windows Vista Enterprise SP1,
	  GNU Emacs 22.3.1 (i386-mingw-nt6.0.6001) of 2008-09-06 on SOFT-MJASON,
	  CVS gnus (updated Nov 17, 2008)

When I'm running Lars' ~/gmadmin/spam-gmane.el to approve and reject
spam reports in www.gmane.org I see the message "No DNS server
configuration found" where I'm supposed to see the reverse lookup of the
reporting machine's IP address.

The spam-gmane.el uses a dns.el that comes from gnus, and the method
that contains the message I see is the method query-dns.

Does anyone know why the query-dns function in Gnus doesn't work as
expected for me?  Is it expected to work at all on Windows machines?  Is
it expected to work at all on Vista machines?

Is there some configuration trick I can do to get a DNS server?

(I obviously _do_ get a DNS server, when I get a DHCP lease... why
doesn't dns.el see that one?)


Thanx!


- Steinar

Re: "No DNS server configuration found" when approving spam reports

[Reiner Steib]

On Wed, Dec 24 2008, Steinar Bang wrote:

> When I'm running Lars' ~/gmadmin/spam-gmane.el to approve and reject
> spam reports in www.gmane.org I see the message "No DNS server
> configuration found" where I'm supposed to see the reverse lookup of the
> reporting machine's IP address.
>
> The spam-gmane.el uses a dns.el that comes from gnus, and the method
> that contains the message I see is the method query-dns.
>
> Does anyone know why the query-dns function in Gnus doesn't work as
> expected for me?  Is it expected to work at all on Windows machines?  Is
> it expected to work at all on Vista machines?

I don't think Windows has /etc/resolv.conf, so I think it is supposed
to work.  On GNU/Linux, I get:

,----[ M-x ielm RET ]
| ELISP> (require 'dns)
| dns
| ELISP> (let (dns-servers)
| 	 (dns-parse-resolv-conf))
| ("..." "192.168.0.1")
| 
| ELISP> (query-dns "www.gnus.org")
| "66.135.33.159"
`----

> Is there some configuration trick I can do to get a DNS server?

Set `dns-servers'?

  (setq dns-servers '("192.168.0.1"))

I'm not sure how to get the address of the DNS server on Windows;
probably `nslookup www.gnus.org' will show it.

Bye, Reiner.
-- 
       ,,,
      (o o)
---ooO-(_)-Ooo---  |  PGP key available  |  http://rsteib.home.pages.de/

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:

> I don't think Windows has /etc/resolv.conf,

That's putting the finger on the problem.  Thanx!

> so I think it is supposed to work.

Hm, well... that's why it doesn't work.  There is no fallback when
/etc/resolv.conf can't be found.

[snip!]
> Set `dns-servers'?

>   (setq dns-servers '("192.168.0.1"))

Right... but this isn't practical to do on a nomad laptop, where the DNS
server usually comes with the DHCP lease.

> I'm not sure how to get the address of the DNS server on Windows;
> probably `nslookup www.gnus.org' will show it.

Indeed it does.  `M-! nslookup www.gnus.org' right now gives me the output:

Non-authoritative answer:^M
Server:  home.lan
Address:  10.0.0.138

Name:    www.gnus.org
Address:  66.135.33.159

(sanitized CR character in the above outout)

The DNS server is that of the ADSL router of the home LAN I'm connected
to. 

I guess a fallback to dns-parse-resolv-conf would be to run nslookup and
parse the output...?  Of course, then the function should be renamed to
reflect what it's doing.
E.g. dns-parse-resolv-conf-or-parse-nslookup-output or something...?

Re: "No DNS server configuration found" when approving spam reports

[Reiner Steib]

On Thu, Dec 25 2008, Steinar Bang wrote:

>>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:
>
>> I don't think Windows has /etc/resolv.conf,
>
> That's putting the finger on the problem.  Thanx!
>
>> so I think it is supposed to work.

Oops, s/is/isn't/ of course.

>> I'm not sure how to get the address of the DNS server on Windows;
>> probably `nslookup www.gnus.org' will show it.
>
> Indeed it does.  `M-! nslookup www.gnus.org' right now gives me the output:
>
> Non-authoritative answer:^M
> Server:  home.lan
[...]
> I guess a fallback to dns-parse-resolv-conf would be to run nslookup and
> parse the output...?  Of course, then the function should be renamed to
> reflect what it's doing.
> E.g. dns-parse-resolv-conf-or-parse-nslookup-output or something...?

Please try the current code:

	* dns.el (dns-set-servers): Renamed from dns-parse-resolv-conf.  Call
	nslookup if resolv.conf isn't available.
	(dns-query): Rename from query-dns.
	(dns-query-cached): Rename from query-dns-cached.

Does spam-gmane.el use the functions `query-dns' or
`query-dns-cached'?  Then they must be renamed there.

Bye, Reiner.
-- 
       ,,,
      (o o)
---ooO-(_)-Ooo---  |  PGP key available  |  http://rsteib.home.pages.de/

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

[cross-posting to gmane.discuss so that other CVS Gnus using spam
 approvers won't get confused]

>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:

> Please try the current code:

> 	* dns.el (dns-set-servers): Renamed from dns-parse-resolv-conf.  Call
> 	nslookup if resolv.conf isn't available.
> 	(dns-query): Rename from query-dns.
> 	(dns-query-cached): Rename from query-dns-cached.

> Does spam-gmane.el use the functions `query-dns' or
> `query-dns-cached'?  Then they must be renamed there.

It uses query-dns-cached.  I've changed it in my copy, I will notify
Lars about that change as well.

Unfortunately it still doesn't work...:-/

(executable-find "nslookup") works, it returns
"c:/Windows/system32/nslookup.exe"

The entire
      (when (executable-find "nslookup")
	(with-temp-buffer
	  (call-process "nslookup" nil t nil "localhost")
	  (goto-char (point-min))
	  (re-search-forward
	   "^Server:[ \t]*\\([0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+\\)" nil t)
	  (setq dns-servers) (list (match-string 1))))
returns a (nil)

Ah... spotted!  It should look like this:
      (when (executable-find "nslookup")
	(with-temp-buffer
	  (call-process "nslookup" nil t nil "localhost")
	  (goto-char (point-min))
	  (re-search-forward
	   "^Address:[ \t]*\\([0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+\\)" nil t)
	  (setq dns-servers) (list (match-string 1))))

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Steinar Bang <sb@dod.no>:

>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:

>> Please try the current code:

>> * dns.el (dns-set-servers): Renamed from dns-parse-resolv-conf.  Call
>> nslookup if resolv.conf isn't available.
>> (dns-query): Rename from query-dns.
>> (dns-query-cached): Rename from query-dns-cached.

>> Does spam-gmane.el use the functions `query-dns' or
>> `query-dns-cached'?  Then they must be renamed there.

> It uses query-dns-cached.  I've changed it in my copy, I will notify
> Lars about that change as well.

> Unfortunately it still doesn't work...:-/
[snip!]
> Ah... spotted!  It should look like this:
>       (when (executable-find "nslookup")
> 	(with-temp-buffer
> 	  (call-process "nslookup" nil t nil "localhost")
> 	  (goto-char (point-min))
> 	  (re-search-forward
> 	   "^Address:[ \t]*\\([0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+\\)" nil t)
> 	  (setq dns-servers) (list (match-string 1))))

Now the dns-set-servers function works in isolation.

(dns-set-servers)
("10.0.0.138")

But the dns-query and dns-query-cached functions still don't work:

(dns-query-cached "www.gnus.org")
"No DNS server configuration found"

Ah... a possible typo on the last line of dns-set-servers:

Perhaps
	  (setq dns-servers) (list (match-string 1))))))
should be
	  (setq dns-servers (list (match-string 1)))))))

I will rebuild and restart Gnus, and try again.

I did a dry run in the *scratch* buffer with a new defun of
dns-set-servers and an evaluation of a dns-query-cached query, and I
still got the "No DNS server configuration found" message, but I'm
trying a complete restart to be sure that no byte compilation stuff is
fooling me...

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Steinar Bang <sb@dod.no>:

> But the dns-query and dns-query-cached functions still don't work:

> (dns-query-cached "www.gnus.org")
> "No DNS server configuration found"

> Ah... a possible typo on the last line of dns-set-servers:
[snip!]
> should be
> 	  (setq dns-servers (list (match-string 1)))))))

> I will rebuild and restart Gnus, and try again.

> I did a dry run in the *scratch* buffer with a new defun of
> dns-set-servers and an evaluation of a dns-query-cached query, and I
> still got the "No DNS server configuration found" message, but I'm
> trying a complete restart to be sure that no byte compilation stuff is
> fooling me...

It's progress of sorts.  Now the Summary buffer of the spam approval
group shows the IP number instead of "No DNS server configuration
found".

When I run the query function in the *scratch* buffer, I get
(dns-query-cached "www.gnus.org")
nil

with the following message in the minibuffer:
 dns: Got an error while trying to talk to 10.0.0.138

Re: "No DNS server configuration found" when approving spam reports

[Reiner Steib]

On Fri, Dec 26 2008, Steinar Bang wrote:

>>> It uses query-dns-cached.  I've changed it in my copy, I will notify
>>> Lars about that change as well.

As the `query-dns' or `query-dns-cached' are not used anywhere else, I
think it isn't worth to add aliases.  (dns.el shouldn't define
functions out of its name space.)

>> Ah... spotted!  It should look like this:
[...]
>> 	   "^Address:[ \t]*\\([0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+\\)" nil t)

[...]

> Ah... a possible typo on the last line of dns-set-servers:
[...]

Yes.  Fixed in CVS.

> When I run the query function in the *scratch* buffer, I get
> (dns-query-cached "www.gnus.org")
> nil
>
> with the following message in the minibuffer:
>  dns: Got an error while trying to talk to 10.0.0.138

I'd suggest to edebug `dns-query' (go to the defun in dns.el and press
`C-u C-M-x'.  Step thru the lines using `SPC' (see the menu "Edebug"
for more commands.

Bye, Reiner.
-- 
       ,,,
      (o o)
---ooO-(_)-Ooo---  |  PGP key available  |  http://rsteib.home.pages.de/

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:

> I'd suggest to edebug `dns-query' (go to the defun in dns.el and press
> `C-u C-M-x'.  Step thru the lines using `SPC' (see the menu "Edebug"
> for more commands.

`C-u C-M-x' is setting a breakpoint in that function, right?  It doesn't
seem to stop in the function for me.

I've tried the following:
 - CVSup'ing the gnus checkout
 - byte compiling the gnus checkout
 - starting a new emacs
 - starting gnus in the new emacs
 - opening the dns.el file and doing `C-u C-M-x' over "defun" in the
   defun form for dns-query
 - entering the spam approval group
 - the group opened without stopping in dns-query
 - exited the group
 - did `M-x load-library dns.el RET' to load the source form of the
   dns.elc file
 - entered the spam approval group again, it did not stop in the
   breakpoint
 - exited the spam approval group
 - once more did `C-u C-M-x' over "defun" in the defun form for
   dns-query (in case the reload/load of dns.el invalidated the earlier
   breakpoint)
 - entered the spam approval group again, it did not stop in the
   breakpoint 

What I'll try now is to exit the emacs alltogether, then start up a
fresh emacs, load-library dns.el, set the breakpoint, start gnus, and
then enter the spam approval group.

But if I've been doing this completely wrong, please let me know...:-)

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Steinar Bang <sb@dod.no>:

>>>>> Reiner Steib <reinersteib+gmane@imap.cc>:

>> I'd suggest to edebug `dns-query' (go to the defun in dns.el and
>> press `C-u C-M-x'.  Step thru the lines using `SPC' (see the menu
>> "Edebug" for more commands.

> What I'll try now is to exit the emacs alltogether, then start up a
> fresh emacs, load-library dns.el, set the breakpoint, start gnus, and
> then enter the spam approval group.

Ok.  Now I've been successful in stopping in the dns-query function.
What I did, was:
 - Start a fresh emacs
 - `M-x load-library dns.el RET'
 - open the dns.el file and do `C-u C-M-x' over "defun" in the defun
   form for the dns-query function
 - start gnus with `M-x gnus-slave RET' (this is written from the master
   gnus emacs...)
 - enter the spam approval group, and this time it stopped in the edebug
   in the dns-query function

The place the dns-query function fails, is in the call to
dns-make-network-process, and in dns-make-network-process the place it
falls is here
    `(let ((server ,server)
when I press SPC when the cursor is placed after the closing parantheses
on the above line.

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Steinar Bang <sb@dod.no>:

>> What I'll try now is to exit the emacs alltogether, then start up a
>> fresh emacs, load-library dns.el, set the breakpoint, start gnus, and
>> then enter the spam approval group.

> Ok.  Now I've been successful in stopping in the dns-query function.
> What I did, was:
>  - Start a fresh emacs
>  - `M-x load-library dns.el RET'
>  - open the dns.el file and do `C-u C-M-x' over "defun" in the defun
>    form for the dns-query function
>  - start gnus with `M-x gnus-slave RET' (this is written from the master
>    gnus emacs...)
>  - enter the spam approval group, and this time it stopped in the edebug
>    in the dns-query function

> The place the dns-query function fails, is in the call to
> dns-make-network-process, and in dns-make-network-process the place it
> falls is here
>     `(let ((server ,server)
> when I press SPC when the cursor is placed after the closing parantheses
> on the above line.

Some more details:
 - Before pressing space, the cursor is positioned over the quote `
 - After pressing space the cursor is positioned over the )
 - The minibuffer displays the text "Result: (car dns-servers)"
 - After the next space the cursor is positioned on top of the
   second-to-last closing parantheses in this line
	 (open-network-stream "dns" (current-buffer) server "domain")))))
   and the minibuffer displays:
Result: (let ((server (car dns-servers)) (coding-system-for-read (quote binary)) (coding-system-for-write (quote binary))) (if (fboundp (quote make-network-process)) (make-network-process :name "dns" :coding (quote binary) :buffer (current-buffer) :host server :service "domain" :type (quote datagram)) (open-network-stream "dns" (current-buffer) server "domain")))

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Steinar Bang <sb@dod.no>:

>> The place the dns-query function fails, is in the call to
>> dns-make-network-process, and in dns-make-network-process the place
>> it fails is here
>> `(let ((server ,server)
>> when I press SPC when the cursor is placed after the closing
>> parantheses on the above line.

> Some more details:
>  - Before pressing space, the cursor is positioned over the quote `
>  - After pressing space the cursor is positioned over the )
>  - The minibuffer displays the text "Result: (car dns-servers)"
>  - After the next space the cursor is positioned on top of the
>    second-to-last closing parantheses in this line
> 	 (open-network-stream "dns" (current-buffer) server "domain")))))
>    and the minibuffer displays:
> Result: (let ((server (car dns-servers)) (coding-system-for-read (quote binary)) (coding-system-for-write (quote binary))) (if (fboundp (quote make-network-process)) (make-network-process :name "dns" :coding (quote binary) :buffer (current-buffer) :host server :service "domain" :type (quote datagram)) (open-network-stream "dns" (current-buffer) server "domain")))

When I run just (dns-make-network-process "10.0.0.138") in the *scratch*
buffer, I get the following stack trace:

Debugger entered--Lisp error: (error "Unsupported connection type")
  make-network-process(:name "dns" :coding binary :buffer #<buffer *scratch*> :host "10.0.0.138" :service "domain" :type datagram)
  (if (fboundp (quote make-network-process)) (make-network-process :name "dns" :coding (quote binary) :buffer (current-buffer) :host server :service "domain" :type (quote datagram)) (open-network-stream "dns" (current-buffer) server "domain"))
  (let ((server "10.0.0.138") (coding-system-for-read ...) (coding-system-for-write ...)) (if (fboundp ...) (make-network-process :name "dns" :coding ... :buffer ... :host server :service "domain" :type ...) (open-network-stream "dns" ... server "domain")))
  (dns-make-network-process "10.0.0.138")
  eval((dns-make-network-process "10.0.0.138"))
  eval-last-sexp-1(t)
  eval-last-sexp(t)
  eval-print-last-sexp()
  call-interactively(eval-print-last-sexp)
  recursive-edit()
  byte-code("჆ऀ䀀윀=Ħ

No :type datagram in emacs on Windows...?

Re: "No DNS server configuration found" when approving spam reports

[Lars Magne Ingebrigtsen]

Steinar Bang <sb@dod.no> writes:

> No :type datagram in emacs on Windows...?

Did you resolve this, or is this still a problem?

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@gnus.org * Lars Magne Ingebrigtsen

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Lars Magne Ingebrigtsen <larsi@gnus.org>:

> Steinar Bang <sb@dod.no> writes:
>> No :type datagram in emacs on Windows...?

> Did you resolve this, or is this still a problem?

It's still a problem.

Re: "No DNS server configuration found" when approving spam reports

[Lars Magne Ingebrigtsen]

Steinar Bang <sb@dod.no> writes:

> Debugger entered--Lisp error: (error "Unsupported connection type")
>   make-network-process(:name "dns" :coding binary :buffer #<buffer *scratch*> :host "10.0.0.138" :service "domain" :type datagram)

Looking at that code in dns.el, it doesn't seem to have changed in
yonks.  Are you using a version of Emacs that now has
`make-network-process' but doesn't support the :type flag?  I wonder how
one could check for that...

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@gnus.org * Lars Magne Ingebrigtsen

Re: "No DNS server configuration found" when approving spam reports

[Steinar Bang]

>>>>> Lars Magne Ingebrigtsen <larsi@gnus.org>:

> Steinar Bang <sb@dod.no> writes:
>> Debugger entered--Lisp error: (error "Unsupported connection type")
>> make-network-process(:name "dns" :coding binary :buffer #<buffer *scratch*> :host "10.0.0.138" :service "domain" :type datagram)

> Looking at that code in dns.el, it doesn't seem to have changed in
> yonks.  Are you using a version of Emacs that now has
> `make-network-process' but doesn't support the :type flag? 

Seems that way.  The emacs-version says:
 GNU Emacs 22.3.1 (i386-mingw-nt6.0.6001) of 2008-09-06 on SOFT-MJASON

So... it'f fairly new.  It's the precompiled emacs from the Windows
emacs FAQ list:
	http://www.gnu.org/software/emacs/windows/Getting-Emacs.html#Getting-Emacs

> I wonder how one could check for that...

Dunno.