> For the complete documentation index, see [llms.txt](https://platform9.com/kb/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://platform9.com/kb/pmo/solution/unable-to-start-pf9-neutron-ovs-agent-service.md).

# Unable to Start pf9-neutron-ovs-agent Service

## Problem

* Starting ***pf9-neutron-ovs-agent*** service on the host fails with the below error

{% tabs %}
{% tab title="None" %}

```none
Could not retrieve schema from tcp:127.0.0.1:6640: Connection refused
```

{% endtab %}
{% endtabs %}

* We can see below errors in host logs:
  * */var/log/pf9/pf9-neutron-ovs-agent.log*

```
2020-04-02 03:19:37.870 5609 ERROR neutron.plugins.ml2.drivers.openvswitch.agent.openflow.native.ovs_ryuapp [-] Agent main thread died of an exception: Exception: Could not retrieve schema from tcp:127.0.0.1:6640: Connection refused
```

*/var/log/syslog.log*

```
Apr 2 03:20:47 osvt02 ovs-vsctl: ovs|00001|db_ctl_base|ERR|unix:/var/run/openvswitch/db.sock: database connection failed (No such file or directory)
```

## Environment

* Platform9 Managed OpenStack - v3.6.0 and Higher
* Neutron

## Cause

***pf9-neutron-ovs-agent*** service was not able to start as Open vswitch Database service(ovsdb-server) is in the stopped state.

{% tabs %}
{% tab title="None" %}

```none
systemctl status ovsdb-server● ovsdb-server.service - Open vSwitch Database Unit Loaded: loaded (/usr/lib/systemd/system/ovsdb-server.service; static; vendor preset: disabled) Active: inactive (dead)
```

{% endtab %}
{% endtabs %}

{% tabs %}
{% tab title="None" %}

```none
$ sudo netstat -tulpn | grep -i 6640$
```

{% endtab %}
{% endtabs %}

## Resolution

1. Start the Open vSwitch Database service( ***ovsdb-server***) on the host manually.
2. Restart ***pf9-neutron-ovs-agent*** service on the host.


---

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