> 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/pmk/frequently-asked-questions/comms-showing----error--err-tl-s-cert-altname-invalid---hostname.md).

# Hostname/IP Does not Match Certificate's altnames Which Breaks the Communication to Management Plane

## Problem

* Comms not able to communicate to management plane and throwing the following error.

{% tabs %}
{% tab title="Comms Log" %}

```javascript
[2023-09-03 14:29:35.144] [ERROR] sni-broker.v0.mgplane.pf9.localnet-::1-5672-4 - TLS socket for client 28180 error: Error [ERR_TLS_CERT_
ALTNAME_INVALID]: Hostname/IP does not match certificate's altnames: Host: broker.v0.mgplane.pf9.localnet. is not cert's CN: mgplane.pf9.localnet
```

{% endtab %}
{% endtabs %}

## Environment

* Platform9 Edge Cloud - v-5.3.0-2075501

## Cause

* Host agent config file is not updated with the `cert_version` parameter which leads comms to use an older cert version.

{% tabs %}
{% tab title="hostagent.conf" %}

```javascript
root@worker0 ~]# cat /etc/pf9/hostagent.conf
[hostagent]

[ssl]
cert_version=
disable=True
```

{% endtab %}
{% endtabs %}

* From error message `[2023-09-03 14:29:35.144] [ERROR] sni-broker.v0.mgplane.pf9.localnet-::1-5672-4 - TLS socket for client 28180 error.`The `sni-broker.v0` indicates it is referring to cert version v0.

## Resolution

* Identify the `latest cert_version.`

{% tabs %}
{% tab title="certs directory" %}

```javascript
[root@mgplane ~]# ls -ltr /etc/pf9/certs/
total 12
drwxr-xr-x  2 root root  109 Mar 30  2022 web_test_ca
drwxr-xr-x 27 root root 4096 Jul  6 04:47 v1
drwxr-xr-x 27 root root 4096 Jul  6 04:47 v2
drwxr-xr-x 27 root root 4096 Jul  6 04:47 v3  <<---- Latest version
```

{% endtab %}
{% endtabs %}

* Update the `hostagent.conf` file

{% tabs %}
{% tab title="hostagent.conf" %}

```javascript
vi /etc/pf9/hostagent.conf

[hostagent]

[ssl]
cert_version=v3 <--- Add the latest version here.
disable=True
```

{% endtab %}
{% endtabs %}

* Restart the services.

{% tabs %}
{% tab title="restart services" %}

```javascript
# systemctl restart pf9-comms.servcie
# systemctl restart pf9-sidekick.servcie
# systemctl restart pf9-hostagent.servcie
```

{% endtab %}
{% endtabs %}

###


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