# sudo addgroup <groupname>
To add a new user to a existing group:
# sudo adduser <username> groupname
Installing available updates on Ubuntu
sudo apt-get upgrade
This will download and install all available updates to your existing system.
Software RAID support on Linux
Good RAID FAQ on Linux here.
Walkthrough on setting up a software RAID array here
Check RAID status:
<code>/sbin/mdadm --detail /dev/md0</code>
Or check with this:
<code>sudo cat /proc/mdstat</code>
This is what a good status will look like:
<code>
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md1 : active raid1 sdb5[0] sdc5[1]
1485888 blocks [2/2] [UU]
md0 : active raid1 sdb1[0] sdc1[1]
242709888 blocks [2/2] [UU]
unused devices: <none>
The [UU] (I think) indicates the status of both drives in the array, and both are Up
Removing drives: sudo mdadm /dev/md0 -r /dev/sdb1
Adding drives back to the array: sudo mdadm /dev/md0 -a /dev/sdb1
Setting up awstats for multiple virtual host logs
I only just realized recently that my apache2 config was outputting logs for my main domain into access.log, and all other virtual hosts into other_vhosts_access.log. As a result, awstats was not picking up hits to the majority of my sites.
To set up awstats to produce stats for each of my stats was relatively easy:
- Config each virtual host in your apache2.conf to have it’s own CustomLog directive:
<code><br />
<VirtualHost *:80><br />
ServerAdmin example@example.com<br />
DocumentRoot /var/www/html/example<br />
ServerName www.example.com<br />
DirectoryIndex index.jsp index.html<br />
CustomLog /var/log/apache2/access_example.log combined<br />
</VirtualHost><br />
</code></p>
<li>Copy your /etc/awstats/awstats.conf to awstats_example.conf – one per each domain where example is the domain name
<li>Edit each awstats.conf and change the log entry to point to the log file you added in the apache2.conf above, change the DataDir to be /var/awstats/example, and SiteDomain to e.g. example.com
<li>Create new subdirs for each DataDir in /var/awstats
<li>Run the stats collection manually to check working:
<pre><code>
sudo /usr/bin/perl /usr/lib/cgi-bin/awstats.pl -update -config=example.com
</code> - Update your cron entry to schedule the log processing, e.g. in /etc/cron.d/awstats:
<code> 0,30 * * * * www-data [ -x /usr/lib/cgi-bin/awstats.pl -a -f /etc/awstats/awstats_example.com.conf -a -r /var/log/apache/access_example.log ] && /usr/lib/cgi-bin/awstats.pl -config=example.com -update >/dev/null </code>
- Add one line for each of the domains you need to collect log stats for. Done!
To access the stats for each of the domains, use the awstats config name passes as a param in the URL:
<code> http://www.example.com/awstats/awstats.pl?config=example.com </code>