# Installation
> Installation and upgrade instructions for Patroni across supported platforms.
---
LLMS index: [llms.txt](/llms.txt)
---
> Source: https://patroni.readthedocs.io/en/latest/installation.html
--------
## Pre-requirements for Mac OS
To install requirements on a Mac, run the following:
```bash
brew install postgresql etcd haproxy libyaml python
```
--------
## Psycopg
Starting from [psycopg2-2.8](https://www.psycopg.org/articles/2019/04/04/psycopg-28-released/) the binary version of psycopg2 will no longer be installed by default. Installing it from the source code requires C compiler and postgres+python dev packages. Since in the python world it is not possible to specify dependency as `psycopg2 OR psycopg2-binary` you will have to decide how to install it.
There are a few options available:
1. Use the package manager from your distro
```bash
sudo apt-get install python3-psycopg2 # install psycopg2 module on Debian/Ubuntu
sudo yum install python3-psycopg2 # install psycopg2 on RedHat/Fedora/CentOS
```
2. Specify one of `psycopg`, `psycopg2`, or `psycopg2-binary` in the [list of dependencies](/docs/patroni/installation#extras) when installing Patroni with pip.
--------
## General installation for pip
Patroni can be installed with pip:
```bash
pip install patroni[dependencies]
```
where `dependencies` can be either empty, or consist of one or more of the following:
etcd or etcd3
`python-etcd` module in order to use Etcd as Distributed Configuration Store (DCS)
consul
`py-consul` module in order to use Consul as DCS
zookeeper
`kazoo` module in order to use Zookeeper as DCS
exhibitor
`kazoo` module in order to use Exhibitor as DCS (same dependencies as for Zookeeper)
kubernetes
[kubernetes](/docs/patroni/kubernetes#kubernetes) module in order to use Kubernetes as DCS in Patroni
raft
`pysyncobj` module in order to use python Raft implementation as DCS
aws
`boto3` in order to use AWS callbacks
jsonlogger
`python-json-logger` module in order to enable [logging](/docs/patroni/config/yaml#log_settings) in json format
systemd
`systemd-python` in order to use sd_notify integration
all
all of the above (except psycopg family)
psycopg3
`psycopg\[binary\]\>=3.0.0` module
psycopg2
`psycopg2\>=2.5.4` module
psycopg2-binary
`psycopg2-binary` module
For example, the command in order to install Patroni together with psycopg3, dependencies for Etcd as a DCS, and AWS callbacks is:
```bash
pip install patroni[psycopg3,etcd3,aws]
```
Note that external tools to call in the replica creation or custom bootstrap scripts (i.e. WAL-E) should be installed independently of Patroni.
--------
## Package installation on Linux
Patroni packages may be available for your operating system, produced by the Postgres community for:
- RHEL, RockyLinux, AlmaLinux;
- Debian and Ubuntu;
- SUSE Enterprise Linux.
You can also find packages for direct dependencies of Patroni, like python modules that might not be available in the official operating system repositories.
For more information see the [PGDG repository](https://www.postgresql.org/download/linux/) documentation.
If you are on a RedHat Enterprise Linux derivative operating system you may also require packages from EPEL, see [EPEL repository](https://docs.fedoraproject.org/en-US/epel/) documentation.
Once you have installed the PGDG repository for your OS you can install patroni.
> [!NOTE]
> Patroni packages are not maintained by the Patroni developers, but rather by the Postgres community. If you require support please first try connecting on [Postgres slack](http://pgtreats.info/slack-invite).
### Installing on Debian derivatives
With PGDG repo installed, see [above](/docs/patroni/installation#package_installation), install Patroni via apt run:
```bash
apt-get install patroni
```
### Installing on RedHat derivatives
With PGDG repo installed, see [above](/docs/patroni/installation#package_installation), install patroni with an etcd DCS via dnf on RHEL 9 (and derivatives) run:
```bash
dnf install patroni patroni-etcd
```
You can install etcd from PGDG if your RedHat derivative distribution does not provide packages. On the nodes that will host the DCS run:
```bash
dnf install 'dnf-command(config-manager)'
dnf config-manager --enable pgdg-rhel9-extras
dnf install etcd
```
You can replace the version of RHEL with `8` in the repo to make `pgdg-rhel8-extras` if needed. The repo name is still `pgdg-rhelN-extras` on RockyLinux, AlmaLinux, Oracle Linux, etc...
### Installing on SUSE Enterprise Linux
You might need to enable the SUSE PackageHub repositories for some dependencies. see [SUSE PackageHub](https://packagehub.suse.com/how-to-use/) documentation.
For SLES 15 with PGDG repo installed, see [above](/docs/patroni/installation#package_installation), you can install patroni using:
```bash
zypper install patroni patroni-etcd
```
With the SUSE PackageHub repo enabled you can also install etcd:
```bash
SUSEConnect -p PackageHub/15.5/x86_64
zypper install etcd
```
--------
## Upgrading
Upgrading patroni is a very simple process, just update the software installation and restart the Patroni daemon on each node in the cluster.
However, restarting the Patroni daemon will result in a Postgres database restart. In some situations this may cause a failover of the primary node in your cluster, therefore it is recommended to put the cluster into maintenance mode until the Patroni daemon restart has been completed.
To put the cluster in maintenance mode, run the following command on one of the patroni nodes:
```bash
patronictl pause --wait
```
Then on each node in the cluster, perform the package upgrade required for your OS:
```bash
apt-get update && apt-get install patroni patroni-etcd
```
Restart the patroni daemon process on each node:
```bash
systemctl restart patroni
```
Then finally resume monitoring of Postgres with patroni to take it out of maintenance mode:
```bash
patronictl resume --wait
```
The cluster will now be full operational with the new version of Patroni.