This guide was last updated in June 2020. View the full changelog.
But, if you’re new to the command line (perhaps you are familiar with CPanel or Plesk?) or you’ve never setup a server from scratch before, you may be wondering what dark magic vudu is required to get up and running.
Well, you’ve come to the right place!
The Command Line Is Hard (…at first)
I’ve set up at least five new servers with Linode and each time I complete the ritual, I learn new incantations that make the Linux angels sing. I’m pretty happy with my current recipe.
Setting up a new server can be confusing, so using a tutorial like this one is a good idea the first time you do it.
Tutorial: How To Set Up Your Linode
In this guide, I will demonstrate how to set up a fresh Ubuntu server from scratch, update everything, install essential software, lock down the server to make it more resilient against basic attacks and denial-of-service, improve server stability, setup automatic backups to another server, and finally install common software like Nginx, MySQL, Python, Node, etc.
A Note About This Guide
I originally compiled this guide as a .txt file of notes for myself, but decided to share it in case anyone finds it useful. If you’re looking for something straight from the horse’s mouth, Linode also offers guides that cover how to set up a new server.
Let’s get started!
Provision a New Linode
First, you need to provision a new Linode. Using Linode’s web UI, it’s quite easy. Select your desired Linode size. If you’re unsure, choose the smallest size. You can always resize it later. You also need to select a location for the server. I usually select “Fremont, CA” since that is closest to my location and the location of most of my users (United States, west coast).
Next, let’s install an OS. Select the “Rebuild” tab. Pick “Ubuntu 18.04 LTS” for the OS image. Use 256MB as the swap disk size (it is default). You’ll be asked to create a password for the
After a few minutes, your server will be ready. Now, click “Boot” to get things started!
Next, let’s connect to the server.
Connecting to Your Server
To connect to your server, type this into your terminal and hit Enter:
Of course, replace
<your server ip> with your Linode’s actual IP address, which you can find on the “Remote Access” tab in the control panel.
This command launches the SSH program and asks it to connect to your server with the username
root, which is the default Ubuntu user. You will be prompted for the
root password you created earlier.
Basic Ubuntu Setup
To set up your new server, execute the following commands.
Set the hostname
Set the server hostname. Any name will do — just make it memorable. In this example, I chose “future”.
Let’s verify that it was set correctly:
Set the fully-qualified domain name
Set the FQDN of the server by editing the
Make sure the following line is in the
/etc/hosts file (after anything that’s in there by default):
It is useful if you add an A record that points from some domain you control (in this case I used “future.<your domain>.net”) to your server IP address. This way, you can easily reference the IP address of your server when you SSH into it, like so:
If you’re curious, you can read more about the
Set the time
Set the server timezone:
Verify that the date is correct:
Update the server
Check for updates and install:
Basic Security Setup
Create a new user
root user has a lot of power on your server. It has the power to read, write, and execute any file on the server. It’s not advisable to use
root for day-to-day server tasks. For those tasks, use a user account with normal permissions.
Add a new user:
Add the user to the
This allows you to perform actions that require
root privilege by simply prepending the word
sudo to the command. You may need to type your password to confirm your intentions.
Login with new user:
Set up SSH keys
SSH keys allow you to login to your server without a password. For this reason, you’ll want to set this up on your primary computer (definitely not a public or shared computer!). SSH keys are very convenient and don’t make your server any less secure.
If you’ve already generated SSH keys before (maybe for your GitHub account?), then you can skip the next step.
Generate SSH keys
Generate SSH keys with the following command:
(NOTE: Be sure to run this on your local computer – not your server!)
When prompted, just accept the default locations for the keyfiles. Also, you’ll want to choose a nice, strong password for your key. If you’re on Mac, you can save the password in your keychain so you won’t have to type it in repeatedly.
Now you should have two keyfiles, one public and one private, in the
If you want more information about SSH keys, GitHub has a great guide.
Copy the public key to server
Now, copy your public key to the server. This tells the server that it should allow anyone with your private key to access the server. This is why we set a password on the private key earlier.
From your local machine, run:
On your Linode, run:
Disable remote root login and change the SSH port
Since all Ubuntu servers have a
root user and most servers run SSH on port 22 (the default), criminals often try to guess the
root password using automated attacks that try many thousands of passwords in a very short time. This is a common attack that nearly all servers will face.
We can make things substantially more difficult for automated attackers by preventing the
root user from logging in over SSH and changing our SSH port to something less obvious. This will prevent the vast majority of automatic attacks.
Disable remote root login and change SSH port:
Set “Port” to “444” and “PermitRootLogin” to “no”. Save the file and restart the SSH service:
In this example, we changed the port to 444. So, now to connect to the server, we need to run:
Update: Somone posted this useful thought about choosing an SSH port on Hacker News:
Make sure your SSH port is below 1024 (but still not 22). Reason being if your Linode is ever compromised a bad user may be able to crash sshd and run their own rogue sshd as a non root user since your original port is configured >1024. (More info here)
Advanced Security Setup
Prevent repeated login attempts with Fail2Ban
Fail2Ban is a security tool to prevent repeated failed login attempts from attackers. It works by monitoring important services (like SSH) and blocking IP addresses which appear to be malicious (i.e. they are failing too many login attempts because they are guessing passwords).
Setup configuration in a new file (will overwrite defaults in
Paste the following into
(Change the port number to match whatever you used as your SSH port).
Save the file and restart Fail2Ban to put the new rules into effect:
Add a firewall
We’ll add an iptables firewall to the server that blocks all incoming and outgoing connections except for ones that we manually approve. This way, only the services we choose can communicate with the internet.
The firewall has no rules yet. Check it out:
Next, we’ll install a package which enables persistent firewall rules. This means that the firewall rules will get automatically applied at server startup:
When prompted, agree to have the current rules installed into
Setup the IPv4 firewall rules in
The following firewall rules will allow HTTP (80), HTTPS (443), SSH (444 (our custom SSH port)), ping, and some ports for testing. All other ports will be blocked.
Paste the following into
*filter # Accept established inbound connections -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT # Allow loopback interface traffic -A INPUT -i lo -j ACCEPT # Reject non-loopback interface traffic to loopback IP addresses -A INPUT ! -i lo -d 127.0.0.0/8 -j REJECT # Allow outbound traffic -A OUTPUT -j ACCEPT # Allow HTTP and HTTPS traffic -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT -A INPUT -p tcp -m state --state NEW --dport 443 -j ACCEPT # Allow SSH connections (Note: --dport should match the port in sshd_config) -A INPUT -p tcp -m state --state NEW --dport 444 -j ACCEPT # Allow ping -A INPUT -p icmp -m state --state NEW -m icmp --icmp-type 8 -j ACCEPT # Allow test ports -A INPUT -p tcp -m state --state NEW --dport 8080:8090 -j ACCEPT # Log denied connections -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7 # Reject all other inbound and forward traffic (default deny unless explicitly allowed) -A INPUT -j REJECT -A FORWARD -j REJECT COMMIT
Setup the IPv6 firewall rules in
Paste the following into
*filter # Accept established inbound connections -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT # Allow loopback interface traffic -A INPUT -i lo -j ACCEPT # Reject non-loopback interface traffic to loopback IP addresses -A INPUT ! -i lo -d ::1/128 -j REJECT # Allow outbound traffic -A OUTPUT -j ACCEPT # Allow ping -A INPUT -p icmpv6 -m state --state NEW -m icmpv6 --icmpv6-type 8 -j ACCEPT # Log denied connections -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7 # Reject all other inbound and forward traffic (default deny unless explicitly allowed) -A INPUT -j REJECT -A FORWARD -j REJECT COMMIT
Activate the firewall rules now:
Verify that the rules were installed correctly:
Restart the server and confirm that the rules are still in place.
Get an email anytime a user uses
I like to get an email anytime someone uses sudo. This way, I have a “paper trail” of sorts, in case anything bad happens to my server. I use a Gmail filter to file these away and only look at them occasionally.
Create a new file for the sudo settings:
Add this to the file:
Set permissions on the file:
This is isn’t mentioned anywhere on the web, as far as I know, but in order for the “mail on sudo use” feature to work, you need to install an MTA server.
sendmail is a good choice:
Now, you should get an email anytime someone uses
Improve Server Stability
VPS servers can run out of memory during traffic spikes or other system events. In this situation, the server might go into “swap hell”. It’s important to configure your applications so memory swapping does not occur.
Modern servers like Nginx or Node.js use a single process to handle multiple simulateous connections, so this is less of a problem than in the past.
For example, in Apache 2.2.x (quite old), the default settings allowed 150 clients to connect simultaneously. This was way too large a number for a typical small VPS server. Let’s do the math. Apache’s processes were typically ~25MB each. If the website got a temporary traffic spike and 150 processes launched, we’d need 3750MB of memory on the server. If we don’t have this much, then the OS will grind to a halt as it swaps memory to disk to make room for new processes, but then immediately swaps the stuff on disk back into memory. This is also known as “swap hell”.
No useful work gets done once “swap hell” occurs. The server can be stuck in this state for hours, even after the traffic rush has subsided. During this time, very few web requests will get serviced.
If you’re still using the ancient Apache 2.2.x for some reason, you could set
MaxClients to something more reasonable like 20 or 30 clients. There are many other optimizations to make, too. Linode has a Library article with optimizations for various server types.
Newer version of Apache (2.4 and up) use an “event based mpm” instead of Apache 2.2 ineffecient “prefork” approach. This is far less of a problem with the improved approach.
And of course, servers like Nginx and Node.js handle thousands of connections without making a new process for each connection.
Reboot server on out-of-memory condition
In cases where something goes awry, it is good to automatically reboot your server when it runs out of memory. This will cause a minute or two of downtime, but it’s better than languishing in the swapping state for potentially hours or days.
You can leverage a couple kernel settings and Lassie to make this happen on Linode.
Adding the following two lines to your
/etc/sysctl.conf will cause it to reboot after running out of memory:
The vm.panic_on_oom=1 line enables panic on OOM; the kernel.panic=10 line tells the kernel to reboot ten seconds after panicking.
Read more about rebooting when out of memory on Linode’s wiki.
These next things are not required but are nice to do.
Set up reverse DNS
The reverse DNS system allows one to determine the domain name that lives at a given IP address. This is useful for network troubleshooting — (ping, traceroute, etc.), as well as email anti-spam measures (read more on Wikipedia).
It’s pretty easy to set up. From the Linode Manager, select your Linode, click on “Remote Access”, then click on “Reverse DNS” (under “Public IPs”). Type in your domain and that’s it!
Set up a private IP address
Private IPs are useful for communicating data on the Linode network, i.e. Linode to Linode. This is handy if you have multiple Linodes (say, one for your web server and one for your database). Private network traffic is more secure (only other Linode customers can see it, vs. the whole internet), faster (the traffic never has to leave the datacenter if both Linodes are in the same datacenter), and free (doesn’t count towards your monthly bandwidth quota).
I currently put my database server on it’s own Linode, so that I can scale it independently of my frontend servers and debug performance issues easier since the systems are isolated. This hasn’t been super-handy yet, but if one of my sites gets a huge traffic rush, I bet it will be immensely useful.
It’s easy to set up. On the Remote Access tab, click Add a Private IP.
Then, just restart the Linode and the new IP address will become available thanks to Linode Network Helper which automatically deposits a static networking configuration in to your Linode at boot.
Configuring your applications and your database to route traffic over the local network is another issue, not covered here.
Install Useful Server Software
At this point, you have a pretty nice server setup. Congrats! But, your server still doesn’t do anything useful. Let’s install some software.
Install a compiler
A compiler is often required to install Python packages and other software, so let’s just install one up-front.
Follow the instructions to install the NodeSource Node.js PPA.
Set root password when prompt asks you.
Verify that MySQL is running.
For connecting to MySQL, instead of the usual PHPMyAdmin, I now use Sequel Pro, a free app for Mac.
Improve MySQL security
Before using MySQL in production, you’ll want to improve your MySQL installation security. Run:
This will help you set a password for the root account, remove anonymous-user accounts, and remove the test database.
Keep your MySQL tables in tip-top shape
Over time your MySQL tables will get fragmented and queries will take longer to complete. You can keep your tables in top shape by regularly running OPTIMIZE TABLE on all your tables. But, since you’ll never remember to do this regularly, we should set up a cron job to do this.
Open up your crontab file:
Then, add the following line:
Also, you can try manually running the above command to verify that it works correctly.
Backup your MySQL databases
automysqlbackup utility can automatically make daily, weekly, and monthly backups of your MySQL database.
Now, let’s configure it. Open the configuration file:
By default, your database backups get stored in
/var/lib/automysqlbackup which isn’t very intuitive. I recommend changing it to a folder within your home directory. To do this, find the line that begins with
BACKUPDIR= and change it to
You also want to get an email if an error occurs, so you’ll know if automatic backups stop working for some reason. Find the line that begins with
MAILADDR= and change it to
MAILADDR="<your email address>".
Close and save the file. That’s it!
Setup Automatic Backups
Backups are really important. Linode offers a paid backup service that’s really convenient if you accidentally destroy something and need to restore your Linode quickly. It’s $5 per month for the smallest Linode. I enable it on all my Linodes.
If you want even more peace of mind (or don’t want to pay for Linode’s backup service) you can roll your own simple backup solution using
You will need access to another Linux server (maybe another Linode?) or a home server. I just installed Ubuntu on an old desktop computer to use as a backup server.
We’re going to create a weekly cronjob that backs up our Linode’s home directory to a backup server. I keep all the files that I would want to backup in my home folder, so this works for me.
Open your crontab:
Add this line to the file:
I recommend running the above command manually to make sure you have it right before adding it to your crontab file.
You can discuss, upvote, or poke fun at this post over at Hacker News.
(If you liked this, you might like Freedom of Speech on the Internet.)