Now, don’t forget that it your SSH into your LISH console, you can see everything going on even with your Linode powered off. Click the Image Options link for the image you wish to resize.

Now, simply type the new disk image size. If you enter a larger number, the image will be expanded. If smaller, the disk image will be shrunk. Additionally, there is no need to worry if you try to shrink or expand beyond what is possible. The resize process will simply fail in such cases and return your disk image to its previous size.

This ability to resize disk images provides a very useful utility to squeeze the full potential of a linode as it evolves over time.

Call me a Linode fan boy!

StackScripts™ provide a flexible way to customize our distribution templates. They’re very easy to use — find a StackScript, answer its questions, and click deploy. When the deployment is first booted, the script is executed and does its thing. You can even watch its progress by viewing the console.

As so many things with Linode.com and its community there is a public library of the Stackscripts available for a variety of purposes. Anything a from a standard LAMP setup to WordPress, Drupal and TRAC/SVN setups.

Already having a Linode up and running, I have also been thinking about re-doing the setup of ourLAMP server. Seeing this as an opportunity to both rebuild our LAMP server and test StackScripts, I set out to give it a try.

We already had a Linode configuration and a disk image actively running. The good news was that when you choose to deploy a new distribution via a stackscript, it will create both a new Linode configuration as well as a new disk image. Doing so keeps you from having to remove the currently running setup.

One of the standard Linode LAMP StackScripts provide a form like the image to the left when executed to deploy a new distribution. MySQL user and password, creation of a default database, as well as root O/S password and such. dec

Once the configuration is created, you now only need to boot into the new configuration. If you are logged into your LISH console, you will see the distribution go through the automated process of the StackScript. In our test case, an Ubuntu 8.04 LTS kernel was booted and installed, system updates installed and applied, postfix installed for local loopback only, MySQL installed and tuned, php installed and tuned and apache2 installed and tuned.

Pretty cool so far. Now, there is plenty left to do to get a fairly decent LAMP going that in our case would run Drupal.

Create a new non-root admin  user account called myadminuser and add to the admin group:

adduser myadminuser
usermod -G admin myadminuser

NOTE: Looks like the admin group is already part of sudoers so your new account has sudo privileges.

Update the timezone:

sudo dpkg-reconfigure tzdata

Secure MySQL services in a quick fashion:

sudo mysql_secure_installation

Enable a few Apache2 modules:

sudo a2enmod deflate
sudo a2enmod expires
sudo a2enmod cache
sudo /etc/init.d/apache2 force-reload

Add a few PHP tools:

sudo apt-get install php5-gd
sudo apt-get install php5-curl
sudo apt-get install php5-cli

Secure SSH daemon by changing the port for SSH and disallow root login:

sudo vim /etc/ssh/sshd_config
-- # Protocol 1
-- Protocol 2
-- ListenAddress 10.54.55.104 #your IP
-- Port 5502 # New port different than 22 and < 65535
-- PermitRootLogin no
-- X11Forwarding no

sudo /etc/init.d/ssh restart

Install the firewall and configure:

sudo apt-get install ufw
sudo ufw default deny
sudo ufw allow http/tcp
sudo ufw allow 5502/tcp
sudo ufw enable
sudo ufw status verbose

Configured PostFix by following pieces of our previous post on PostFix and domain forwarding.

sudo vim main.cf
-- See article referenced
sudo vim virtual
-- See article referenced
sudo postmap virtual
sudo ufw allow 25/tcp
sudo postconf -e "inet_interfaces = all"
sudo /etc/init.d/postfix restart

Lastly upon reboot we noticed that mysqld was failing. The problem was that mysqld was not binding correctly. We editing the my.cnf file and added BindAddress 127.0.0.1 above our existing BindAddress 10.54.55.104. This allows mysqld to bind and listen to both local loopback and the external IP (if needed)

At this point, we had not installed APC or MemCached yet. Performance was quite good with this setup and the minimal memory available to this test Linode. We ran six(6) Drupal , one (1) WordPress and one (1) CMS Made simple site with sub-second response times under fairly good load.

Kudos to Linode.com on their StackScript concept. I can certainly see this being very appealing for providers needing to crank out Linodes with a standard configuration for customers.

Blessings.

For our sites, we like Gmail. So I want all my domains to be sent to my Gmail account. This is where we need to setup postfix to forward email for these domain names to a few Gmail account. Below we talk about how we made it happen.

To back up a few steps, I’ll explain what was already installed. We chose to use postfix instead of sendmail because of the security issues surrounding sendmail.

sudo apt-get install postfix

sudo dpkg-reconfigure postfix

Setup Domain Catch-all Aliases

We chose the Internet Site option, set postfix mail domain to our domain name (e.g. example.com). Hmmmm…. so why is it not working. Remember in the previous article I said it had been many moons since I did Unix or Linux admin? Well, I guess I should have added that I have never setup a mail server on Linux.

Thanks to the first two sections of this article we got email working.

Step 1.

sudo vi /etc/postfix/main.cf

and change this to myhostname to localhost

myhostname = localhost

Step 2

Add the following lines to the main.cf file as well.

virtual_alias_domains = example1.com example2.com
virtual_alias_maps = hash:/etc/postfix/virtual

The virtual_alias_domains is a space separated list of the domain names that you want postfix to handle mail for.

Step 3

Now we need to create the virtual alias map file

cd /etc/postfix
sudo vi virtual


Now you have just created the file named virtual. Add a mapping of where to send the emails for the various domains and email addresses.

First we will deal with the catch all forwarding. The format is the domain name then a space and then the email address you want all emails to go to if they don’t match a particular email address.

@example1.com myusername@gmail.com
@example2.com myusername@gmail.com

Next you can add specific email address mappings instead of the catch alls. This format is similar and starts with the specific domain email address, a space and then the forwarder email address.

admin@example1.com myusername@gmail.com
webmaster@example1.com otheruser@gmail.com

Step 4

Now we need to create the hash map the speeds up how postfix reads these virtual mappings.

cd /etc/postfix
sudo postmap virtual

Step 5

Finally we restart postfix

sudo /etc/init.d/postfix restart

Networking

Woohoo, we are now sending email….short-lived celebration though. Still not receiving email to these addresses from outside the server. hmmmm….

Okay, I’m not a rocket scientist. After about 15 minutes of checking config files, logs and such I finally just tried to telnet to port 25 on the server. Yup, no answer at all.

In my haste to lock down the server last week, I had not opened port 25. A quick change to the firewall and we are good to go. Sending and receiving emails for the mapped domains works wonderful.

sudo ufw allow 25/tcp


You could stop here, but again, I’m a bit paranoid.

Use this tool to ensure you are not a bad netizen by providing an open relay server.

Blacklist with Linode IP?

Now, this last bit was specific to our Linode service and the IP address assign in the specific datacenter we are located in. Your mileage may vary. It was noticed that when sending email to a particular user, the message was returned with a 554 message rejected response.

A bit more investigation and we found that the reason was due to our ip address being listed in the SORBS database. Apparently our IP is registered as being a Dynamic User/Host List (DUHL). Essentially, they think it is a dynamically assigned IP address such as those used for home ISP users. A little bit of reading and we submitted our request to have our IP address de-listed. I guess we’ll have to wait a bit to see what happens.

Blessings.

This week we got fed up with such terribly sporadic performance on a MediaTemple grid server account. After many months of watching performance go from acceptable to abysmal, we finally said “enough” with a few sites that were running on this account.

We had just finished doing a major migration of another few of sites to a new MediaTemple Rage dedicated virtual server. The DV’s at MediaTemple are fantastic. After a day of tuning and tweaking, those sites are humming. But, I think this is what really caused the decision to leave the grid server account for some other sites. Grid server performance was terrrible if you site was not a significantly active site.

After a bit of digging, I decide to try my hand at the Linode.com VPS route. Linode.com has long been praised in Drupal circles for their value/performance proposition. Essentially a Linode is a linux virtual server in a Xen environment. Now, please note that this is not for the faint of heart. These are raw server distributions. No web server, mysql, php, control panel pre-installed. You are building your linux server from scratch. Be fore-warned.

It’s been many moons since I did Unix admin work, let alone Linux. I’ve been spoiled by Plesk and cPanel with most hosts. So this was certainly a challenge. Linode provides some very basic tutorials for getting your LAMP server setup in your choice of linux distributions. Again, these tutorials are very basic and will not suffice for long term hosting and certainly don’t secure your server.

One nice thing about Linode.com is a very active community in both their forums and IRC (#linode). I popped into irc and asked a few basic questions. I got some decent help right away, along with the usual, “stupid noobie” style remarks. Oh well, ignore the chaff.

Upon signing up for my Linode 540 I had a running server in about 34 minutes. Of course, I learned a few things, trashed it and made a new server. Man, my command line Apache2 skills have vastly improved in the last 24 hours.

Luckily I could just “rsync” all the files for a site from the old grid server, directly to my new linode super fast. Mysql db backup and then resotred to the linode server. Then I edited my /windows/system32/drives/etc/host file to point www.myexample.com to the new linode IP. This let me test the site on the linode server without changing DNS for the time being. (Heck, you don’t want your sites down, right?)

I typed the url into my browser and in less than 1 second the page was rendering. Wow! Now compare that to the 15 second lag time on the grid server for a first time hit. Incredible. Of course, I had to run through lots of site pages just to keep seeing that great response time.

Now for my test installation I went with Ubuntu 8.04 LTS OS image. Then, this great Aegir prep article on Drupal.org was used as a basis for the install. The only difference was that that instead of manually installing Apache2 and Mysql I installed the lamp-server^ package which does this and more for you. (Don’t forget the ^ carrot as part of the package name.)

sudo apt-get install lamp-server^

I also found that a particular plugin for WordPress needed curl instead of wget. So a quick install of php5-curl did the trick.

sudo apt-get install php5-curl

For those that don’t want to deal with command line might want to look at the VirtualMin GPL product which provides a web based interface to manage your hosting sever. The automatic install is a breeze but you’ll need to do some reading to understand how to create your first virtual server and such. For us, we stuck to the command line.

One thing that I guess I didn’t get right away was that one linode package equals a single linux server. The reason for this is that I’m used to VMware environments where it is nothing to bring up a new VM on any one host. For some reason my brain was thinking of the linode as the host, not the guest. Oh well. My bad for adding a second ip address to my account, create new disk images and then realize, “How do I boot this second system?”. Doh! You can’t.

Of course, it is easy enough order another linode and move disk images between linodes. Also, Linode bills per month (or annually) but you get credit for days not used. So…you can add a linode to create a new “hosting server”, set it up the way you want it, migrate everything from your current linode and then delete the old linode. Doing this, will credit you for the unused days in the billing cycle for the old linode. Essentially, you pay for each days use which is great for minimal cost + flexibility.

On average, a Linode 360 host has 40 Linodes on it. A Linode 540 host has on average 30. Linode 720 host: 20 Linodes; Linode 1080 host: 15; Linode 1440 host: 10; Linode 2880: 5.

Another exciting item is the announced Linode API. This new api is clean and provides 30+ methods for managing Linode accounts. I am interested at looking into this more and could easily see someone building a module for Aegir to provision more Linodes as needed for new Drupal sites, etc… This has got to have quite a big potential for folks wanting to automate Drupal hosting but want to stay away from the Plesk and cPanel type offerings.

As for flying, on the MediaTemple (gs) account, it would average between 2-10 seconds (2000+ ms) for TTFB for a lightly used site. Now the same site is pulling 400-800 ms TTFB. Now that’s a difference and in my opinion worth the extra administration. Even our MediaTemple (DV) rage is pulling TTFB of around 600-800 ms.

Linode 540              $39.95/mo     400-800 ms TTFB
MediaTemple (gs)        $20.00/mo     > 2000 ms TTFB
MediaTemple (dv) Rage   $100.00/mo    600-800 ms TTFB

All in all, the linode service has been great, performance superb and freedom impressive. Only time will tell how well this will stay this way, but judging by the many others praising Linodes, the ride should be sweet.

Linode Drupal references:

• http://drupal.org/node/194971
• http://drupal.org/node/547910
• http://www.rundrupal.com/linode-review
• http://www.linodereview.com/linode-drupal
• http://hostingfu.com/article/linode-xen-vps-review
• http://www.jeffbeeman.com/node/23

Recent write-up

• http://www.ddj.com/hpc-high-performance-computing/219401166