# Upgrading Ubuntu 16.04 to Ubuntu 18.04

This article walks through the process of upgrading an Ubuntu 16.04 (Xenial) host running OpenStack workloads to 18.04 (Bionic).

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**Note**

Ubuntu 16.04 is now deprecated and will not be supported with the next (5.3) release of Platform9 Managed OpenStack.
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## Steps

### Prepare the host for the upgrade

Ensure that you are running Platform9 version 4.2.0 or later. Please [reach out to Platform9 support](https://support.platform9.com/hc/en-us/requests/new?ticket_form_id=360000931054) to upgrade.

If you have workloads running on this host, you will need to either gracefully shut down the workloads or live-migrate them to another host before you proceed. Please refer to these guides to live-migrate [volumes](https://support.platform9.com/hc/en-us/articles/360010715314-Migrating-Cinder-Volumes-in-a-LVM-Storage-Backend) and [instances](https://github.com/platform9/pcd-docs-gitbook/blob/main/other-docs/pmo/5.8/preparing-ubuntu/virtual-machines-live-migrate.md).

### Package/Kernel Upgrades

1. Upgrade packages on 16.04 to their latest version.

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{% tab title="Bash" %}

```bash
sudo apt update
sudo apt upgrade
```

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2. Reboot the host if there were kernel upgrades.

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```bash
sudo reboot
```

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### Disk Cleanup

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**IMPORTANT**

Remember to have at least **20GB** of free disk space under your root partition `/` before you begin the upgrade. A good place to cleanup is `/boot` which stores all previously installed kernels; the older kernels are safe to delete.
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1. Identify the current kernel version used.

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{% tab title="Bash" %}

```bash
uname -a
```

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2. Fetch the list of available kernels.

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```bash
dpkg --list | grep linux-image
```

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3. Cleanup all kernels with versions lower than your current kernel version.

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```bash
sudo apt-get purge linux-image-x.x.x.x-generic
```

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**Info**

We use `do-release-upgrade` to upgrade to the next LTS release. For recoverability in case of failure, `do-release-upgrade` opens another SSH session on port `1022`. If you have a firewall blocking access to that port, you would need to open that up now.
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For example, if you are using `ufw`:

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{% tab title="Bash" %}

```bash
sudo ufw allow 1022/tcp
```

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Alternatively, if you use `iptables`:

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{% tab title="Bash" %}

```bash
iptables -I INPUT -p tcp --dport 1022 -j ACCEPT
```

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### Upgrading to Ubuntu 18.04

1. Once the packages installed have all been upgraded to their latest versions, kickoff the Ubuntu upgrade to the next LTS version - which, in this case, is 18.04.

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{% tab title="Bash" %}

```bash
sudo do-release-upgrade
```

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{% endtabs %}

<figure><img src="https://2491133324-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTp3vmrOuO3dQilOzN2fE%2Fuploads%2Fgit-blob-6f281f864ecd9149dad1f119e5d6d650a62b308e%2F1604969830.png?alt=media" alt=""><figcaption></figcaption></figure>

2. This fetches the updated package list for bionic and prompts you to continue to begin downloading packages.

<figure><img src="https://2491133324-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTp3vmrOuO3dQilOzN2fE%2Fuploads%2Fgit-blob-192e70d3e6c2a557703d483a799d5126986e41d2%2F1604969874.png?alt=media" alt=""><figcaption></figcaption></figure>

3. As the installation proceeds, you will be periodically prompted to choose if you want an updated config file for various services. Remember to pick `keep the local version currently installed.`

<figure><img src="https://2491133324-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTp3vmrOuO3dQilOzN2fE%2Fuploads%2Fgit-blob-1ccc3bbbeb35a857b2bdc05b32071257cb61aaf6%2F1604969968.png?alt=media" alt=""><figcaption></figcaption></figure>

4. Once the installation completes, reboot the host.