Sunday, September 14, 2008

Mounting home on a different partition

I recently did a reinstall of Ubuntu and rather than loosing all my personal data and having to copy it all back from the backup server, decided to put /home on a separate partition, leaving the rest of the drive for Ubuntu.

Thanks to the help on the Ubuntu blog, I got it set up and running with no problems, leaving a quick mount after the reinstall to get think back up and running. No more faffing around trying to get the machine setup as it was before... all the app specific information is already where it needs to be.
sudo -s
move /home /home1
mkdir /home
mount /dev/sda1 /home
joe /etc/fstab

/dev/sda1 /home ext3 nodev,nosuid 0 2

Saturday, August 02, 2008

Find and remove

Was needing to find all the .jpg files in my music folder and remove them - good old terminal...:
find -name "*.jpg" -exec rm {} \;

Friday, August 01, 2008

Hiding apache and PHP version numbers

Finally figured out how to hide the fact that apache and PHP weren't the latest version. Needed to do this becuase of PCI checking on the server which doesn't taken into account that the non-latest versions of the software have backported security.

Apache:

edit /etc/apache2/apache.conf and set:
ServerSignature Off
ServerTokens Prod
PHP:

edit php.ini and set:
expose_php = Off
For plesk, the php.ini file is in /usr/local/psa/admin/conf on a Debian related system. The httpd.conf file is in this directory too.

Wednesday, July 09, 2008

Terminal based IP traffic monitor

I'd been looking for a terminal based IP traffic monitor for a while but had never found one fit for purpose.

Not sure where I was looking though, because I found this fine little package: iptraf. It's not the prettiest thing in the world, but it works and works well.

automating mysqltuner

I found the mysqltuner a while back and had been using it on one of my servers sporadically. I suddenly thought... why don't I run it automatically via a cron every week and test the server optimisation. Easy...
sudo -s
wget http://mysqltuner.com/mysqltuner.pl
chmod +x mysqltuner.pl
cp ./mysqltuner.pl to /usr/local/bin/mysqltuner
Ensure that it's in the right place by running it and then optimise the current mysql server and restart it:
mysqltuner
joe /etc/mysql/my.cnf
/etc/init.d/mysql restart
Now we need to add a cron entry to make it run every week.
crontab -e
43 4 * * * thur mysqltuner
And that's it, saving the crontab file will install it and on the next thursday at 4:43 in the morning, the optimiser will run as root and email the server admin the output.

Saturday, July 05, 2008

Multiple apache sites on localhost

I do all my application development locally, but for a while haven't needed to have two instances of locally running applications. In the past, I had setup apache to serve multiple local instances, but I hadn't written down the process.

First of all, alter /etc/hosts to add a line for your new site.
127.0.0.1 localhost.localdomain localhost<br />127.0.0.2 localccc.localdomain localccc
Then, alter the apache config: create a file per site in /etc/apache2/sites-available:
<VirtualHost localhost>

ServerName localhost
ServerAdmin webmaster@localhost
ServerSignature On

DocumentRoot /home/elements/htdocs/

<Directory>
Options FollowSymLinks
AllowOverride None
</Directory>

<Directory home/elements/htdocs/>
Options Indexes FollowSymLinks MultiViews
AllowOverride All
Order allow,deny
allow from all
</Directory>

ErrorLog /var/log/apache2/error.log
CustomLog /var/log/apache2/access.log combined
LogLevel warn

</VirtualHost>
Also remove the contents of default: just empty it.
Then enable the sites you've created (run it once for each filename you've created):
a2ensite localhost
Finally, restart the server
/etc/init.d/apache
And, as Gordon Ramsay would say... DONE.

Thursday, July 03, 2008

PCI compliance

Some of my clients are being hassled with these new PCI checks... not that they're really all that new, but PDQ companies are certainly using them a lot more.

A really helpful article can be found here: Making Plesk more PCI compliant

On the last check, the servers were failing on several fronts, and I thought I'd note down some pointers for the future.

1.
SSH host keys. Being Debian, the servers fell fowl of a packaging mistake with SSH in which the keys became less than secure... need to re-generate them.
sudo -s
rm /etc/ssh/ssh_host_*
dpkg-reconfigure openssh-server
Then all you need to do is go around the update all the known_host files... yawn

2.
PHP version. Problem with Plesk 8.4 is that is uses one version of PHP for Apache and one for the control panel. And, the version used for the control panel was horribly out of date.

The version used for the forward facing pages is not completely up to date either, so I've used the dotdeb repros to get the latest versions.
sudo -s
joe /etc/apt/sources.list
deb http://dotdeb.netmirror.org/ stable all
deb-src http://dotdeb.netmirror.org/ stable all
apt-get update
apt-get upgrade
Make sure that you keep your old config files, or at least do a diff to work out which bits have been changed.

The version that is used for the Plesk control panel is independant on that installed on the system and is shipped separately. According to the Forum, it will be upgraded to 5.2.6 from the next release... 8.5... whenever that will be... have posted to the thread to find out.

As well as this, the scores for psa were being counted twice because port 8880 and port 8443 were both open and creating the same errors. As far as I can tell, port 8880 isn't used in a standard setup. So, until the next release, I thought I'd just try and block its use.
sudo -s
joe /opt/psa/admin/conf/httpds.conf
#Listen 8880
/etc/init.d/psa restart
You can then test the connection to port 8880 from a remote location.
telnet servername 8880

3.

Somebody had left a phpinfo() file in a forward facing position. (5 points)

4.
Apache needs to be over 2.2.8 and if it's not, that's another 6 points.

5.
Port 53 was open
Close it using the Firewall module in Plesk (DNS server)

6.
SSL 2.0 was being used... that added another 4 points.
sudo -s
joe /etc/apache2/httpd.conf
SSLCipherSuite ALL:!ADH:!LOW:!SSLv2:!EXP:+HIGH:+MEDIUM
SSLProtocol all -SSLv2
/etc/init.d/apache2 restart
You also need to alter the psa (Plesk Server Admin):
sudo -s
/opt/psa/admin/conf/httpsd.custom.include
SSLCipherSuite ALL:!ADH:!LOW:!SSLv2:!EXP:+HIGH:+MEDIUM
SSLProtocol all -SSLv2
/etc/init.d/psa restart
(If the .custom.include file doesn't exist, create it: it will ensure that the config changes persist on package upgrade)

You can double check that the server doesn't respond to a SSL2.0
openssl s_client -connect hostname:443 -ssl2
openssl s_client -connect hostname:8443 -ssl2
openssl s_client -connect hostname:25 -starttls smtp -ssl2
If SSL2.0 is disabled, you should get the following returned.
419:error:1407F0E5:SSL routines:SSL2_WRITE:ssl handshake failure:s2_pkt.c:428:

420:error:1406D0B8:SSL routines:GET_SERVER_HELLO:no cipher list:s2_clnt.c:450:
.