How to Upgrade to Ubuntu 16.04 LTS

Ubuntu 16.04 is a Long-Term Support (LTS) release that will be supported by Canonical until April 2021. This guide explains how to upgrade your Linode from Ubuntu 14.04 (Trusty Tahr) to Ubuntu 16.04 (Xenial Xerus).

Caution

Distribution upgrades sometimes yield unpredictable results. If possible, use these steps as an alternative to the upgrade method described in this guide:

• Create a new Linode with the latest disk template
• Rebuild your stack
• Transfer your data
• Swap IP addresses

The upgrade may be incomplete or your system may be corrupted if your internet connection is interrupted. Use Lish or Glish to perform this upgrade in a stable environment that does not rely on an active internet connection to your Linode.

Important: Ubuntu 16.04 ships with OpenSSH 7.2p2, which does not allow ssh-dss host authentication, or use of the SSH version 1 protocol.

Note

The steps required in this guide require root privileges. Be sure to run the steps below as root or with the sudo prefix. For more information on privileges see our Users and Groups guide.

In order to prepare you Linode for upgrade, the following steps will:

1. Install updates for Ubuntu 14.04

2. Backup your data

3. Ensure that the kernel version you’re using is the latest

4. Stop non-critical services

5. Start a LISH session to ensure that the installation is not interrupted

Update package lists and install all updates:

apt-get update && apt-get upgrade

It’s a good idea to back up your Linode before performing a major upgrade. That way, you can restore from backup if anything goes wrong during the upgrade process. If you subscribe to the Linode Backup Service, we recommend that you take a manual snapshot before upgrading to Ubuntu 16.04 LTS. If you use another backup service or application, we recommend that you make a manual backup now.

Verify that your Linode is using the latest supported kernel. See Applying Kernel Updates for more information.

We recommend that you stop as many services as possible before upgrading to Ubuntu 16.04 LTS. This includes web server daemons (Apache and nginx), database servers (PostgreSQL and MySQL), and any other non-critical services. To stop a service, enter the following command, replacing apache2 with the name of the service you want to stop:

service apache2 stop

You are now ready to install Ubuntu 16.04 LTS on your Linode.

Remember to perform these steps in a Lish or Glish session:

1. Install the update-manager-core package:

   apt-get install update-manager-core
   

2. Open /etc/update-manager/release-upgrades and verify that the Prompt value is set to lts:

   File: /etc/update-manager/release-upgrades

   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

   # Default behavior for the release upgrader. [DEFAULT] # Default prompting behavior, valid options: # # never - Never check for a new release. # normal - Check to see if a new release is available. If more than one new # release is found, the release upgrader will attempt to upgrade to # the release that immediately succeeds the currently-running # release. # lts - Check to see if a new LTS release is available. The upgrader # will attempt to upgrade to the first LTS release available after # the currently-running one. Note that this option should not be # used if the currently-running release is not itself an LTS # release, since in that case the upgrader won't be able to # determine if a newer release is available. Prompt=lts

3. You’re now ready to begin the upgrade to Ubuntu 16.04 LTS:

   do-release-upgrade
   

   Follow the on-screen instructions to complete the installation process.

4. Because Linode offers internal package mirrors for Ubuntu, you may see this message:

   No valid mirror found
   
   While scanning your repository information no mirror entry for the
   upgrade was found. This can happen if you run an internal mirror or
   if the mirror information is out of date.
   
   Do you want to rewrite your 'sources.list' file anyway? If you choose
   'Yes' here it will update all 'trusty' to 'xenial' entries.
   If you select 'No' the upgrade will cancel.
   
   Continue [yN]
   

   Type y and Enter to continue.

5. The upgrade will require a reboot. Once the system has rebooted, verify that it’s running Ubuntu 16.04:

   lsb_release -a
   

6. You should see output that resembles the following:

   No LSB modules are available.
   Distributor ID: Ubuntu
   Description:    Ubuntu 16.04 LTS
   Release:        16.04
   Codename:       xenial
   

Your Linode is now running Ubuntu 16.04 LTS.

If your Linode is running a release of Ubuntu older than 14.04 LTS, use the upgrade guides in the Upgrading section to upgrade to Ubuntu 14.04 LTS first. You may then upgrade your Linode to Ubuntu 16.04 LTS.