Category: Technical

If you ever get an error like this.

W: GPG error: http://non-us.debian.org stable/non-US Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY F1D53D8C4F368D5D
W: You may want to run apt-get update to correct these problems

The way I solved it was as follows. As root…

# apt-get install gnupg
# gpg –keyserver wwwkeys.eu.pgp.net –recv-keys F1D53D8C4F368D5D
# gpg –armor –export F1D53D8C4F368D5D | apt-key add –
# gpg –export F1D53D8C4F368D5D >> /etc/apt/trusted.gpg
# gpg –list-keys

Not sure if anyone else has noticed recently but Slurp has been doing a lot of of Spidering lately. I actually took extreme measures today and added a crawl delay to the site.

I have been writing a test suite for a website recently and came upon the following error.

Illegal value ‘GBR’ for field ‘country_iso’ at /usr/local/share/perl/5.8.4/WWW/Mechanize.pm line 1232

This seemed strange to me at first but when I thought about it I was using the following code

$mech->select(“country_iso”, ‘GBR’ );

If the value i.e. “GBR” in my case is not a valid select option then obviously WWW::Mechanize or rather HTML::Form will throw an error. It was actually HTML::Form::ListInput that the error came from but this is a package declared in the HTML/Form.pm module.

If you are running Apache in a chroot env and you receive something like this.
null: Had to create DBD::Pg::dr::imp_data_size unexpectedly at /usr/local/lib/perl/5.8.4/DBI.pm line 1190
One cure is to make sure you have copied all your PostgreSQL library files into the directory in your chroot environment.

A good command for testing if your TLS setup works in exim4 is:
swaks -s insert.host.name.here -tls -q ehlo
It goes something like this.
~$ swaks -s insert.host.name.here -tls -q ehlo
=== Trying insert.host.name.here:25…
=== Connected to insert.host.name.here.
EHLO debian
<- 250-insert.host.name.here Hello somewhere.com [81.107.112.224]
<- 250-SIZE 52428800
<- 250-PIPELINING
<- 250-AUTH PLAIN_TEXT LOGIN
<- 250-STARTTLS
STARTTLS
EHLO debian
<~ 250-insert.host.name.here Hello cpc2-cable.ntl.com [8.0.1.4]
<~ 250-SIZE 52428800
<~ 250-PIPELINING
<~ 250-AUTH PLAIN_TEXT LOGIN
QUIT
<~ 221 insert.host.name.here closing connection

If you get the above when inspecting the putput from your SMTP server then you most likely have something inspecting your SMTP or ESMTP traffic. In my case it was a CISC0 851 router. I believe a most CISCO gear especially PIX firewalls are culprits for this. Below is what I was getting:
250-SIZE 52428800
250-PIPELINING
250-AUTH PLAIN_TEXT LOGIN
250-XXXXXXXA
250 XXXB
starttls
500 unrecognized command
If you want to see a genuine output from a server try the following.
debian:~# telnet YOURSERVER.COM 25
Trying 8.8.8.9…
Connected to YOURSERVER.COM.
Escape character is ‘^]’.
220 YOURSERVER.COM ESMTP Exim 4.5 Sun, 21 Jan 2007 19:16:18 +0000
When you see the above, enter:
EHLO [10.10.10.8]
and the following will be the output.
250-YOURSERVER.COM Hello me.org [81.107.112.224]
250-SIZE 52428800
250-PIPELINING
250-AUTH PLAIN_TEXT LOGIN
250-STARTTLS
250 HELP
Then type:
STARTTLS
to see.
220 TLS go ahead
This means your encrypted link to the server is working.
Have fun.

If you get the following error when testing TLS.
TLS error on connection from … (DH params import): Base64 decoding error.
Regenerate your /var/spool/exim4/gnutls-params file. You may have upgraded exim and it can no longer read the file. See:
http://www.mail-archive.com/exim-dev@exim.org/msg01219.html

If you are wondering where your rrdtool library is and are sure it is not here.
/usr/local/rrdtool/lib
try
/usr/lib/

While trying to get exim4 using TLS I noticed an odd problem. For some reason /dev/random was not generating a lot of output due to a lack of entropy. I do not fully understand the problem but it meant that exim4 was being blocked when generating the RSA key. I tried changing from a 2.4.32 kernel to a 2.6.16.27 kernel and this seemed to generate more random data but it still wasn’t sufficient.
I resorted to editing my
/etc/cron.daily/exim4-base
commenting out the last line that deletes
/var/spool/exim4/gnutls-params
I then ran
find / -type f | xargs cat > /dev/null
to generate a lot of noise on the system.
hal:~# swaks -a -tls -q HELO -s localhost -au harry
Password:
=== Trying localhost:25…
=== Connected to localhost.
EHLO hal.vm.bytemark.co.uk
<- 250-hal.vm.bytemark.co.uk Hello localhost [127.0.0.1]
<- 250-SIZE 52428800
<- 250-PIPELINING
<- 250-STARTTLS
STARTTLS