> For the complete documentation index, see [llms.txt](https://support.portsip.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.portsip.com/v16.x-maintenance-mode/high-availability-v16.x/high-availability-for-on-premise/upgrading-high-availability-installation.md).
# Upgrading High Availability Installation
{% hint style="info" %}
Before upgrading the PBX HA, please consult with PortSIP support to ensure the versions are compatible.
{% endhint %}
Please follow the below steps to upgrade your current PBX HA.
## Back up data
Before upgrading, please back up the PBX data.
1. Stop the PBX service
Perform the below command only on the **pbx01.**
```sh
cd /opt/portsip-pbx-ha-guide && sudo /bin/bash ha_ctl.sh stop -s pbx
```
2. Check the current master node
Perform the below command only on the **pbx01.**
```sh
cd /opt/portsip-pbx-ha-guide && sudo /bin/bash ha_ctl.sh master
```
For example, the below output indicates the current master node is **pbx01**.
3. Back up data
Log in to the current master node, and back up the PBX data directory: `/var/lib/portsip`
## Download and update resources
Perform the below command only on the **pbx01.**
```sh
cd /opt && rm -rf portsip-pbx-ha-guide-16-online.tar.gz && \
sudo wget -N https://www.portsip.com/downloads/ha/v16/portsip-pbx-ha-guide-16-online.tar.gz \
&& sudo tar xf portsip-pbx-ha-guide-16-online.tar.gz
```
## **Update**
Use the new version image of PortSIP PBX to update the PBX.
{% hint style="danger" %}
Please contact PortSIP support to obtain the **\** before upgrading.
{% endhint %}
Perform the below command only on the **pbx01.**
cd /opt/portsip-pbx-ha-guide/ && /bin/bash update.sh <PortSIP PBX new version image>
For example:
```sh
cd /opt/portsip-pbx-ha-guide/ && /bin/bash update.sh portsip/pbx:16.4.4.2814-release
```