---
title: "Check SSL/TLS Versions"
canonical: "https://wiki.patientsknowbest.com/space/api/4493377557/Check%20SSL%2FTLS%20Versions"
format: markdown
---
> Macro (toc)

# Instructions

> 📝 Following instruction on this page you can test if your client has support for one of the SSL/TLS versions required by our servers.

On the host that runs your service run the next command:

```
curl -o /dev/null -s -vvv https://my.patientsknowbest.com
```

# Expected Success Output

```
*   Trying 35.246.122.93:443...
...
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
...
* Connection #0 to host my.patientsknowbest.com left intact
```

> ✅ `SSL connection using TLSv1.3` indicates that your host OS is supports `TLSv1.3` which is one of the TLS versions our servers also support.

> ℹ️ **TIP**: Version of your integration engine running on the given host might not support any of the SSL/TLS version that our servers require.

> ℹ️ **NEXT**: Consult documentation of your integration enginge to see what SSL/TLS versions it supports.

# Expected Failure Output

```
*   Trying 35.246.122.93:443...
* Connected to my.patientsknowbest.com (35.246.122.93) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
*  CAfile: /etc/ssl/certs/ca-certificates.crt
*  CApath: /etc/ssl/certs
* TLSv1.2 (OUT), TLS header, Unknown (21):
} [5 bytes data]
* TLSv1.3 (OUT), TLS alert, protocol version (582):
} [2 bytes data]
* error:0A0000BF:SSL routines::no protocols available
* Closing connection 0
```

> ❌ `error:0A0000BF:SSL routines::no protocols available` indicate that TLS versions supported by the client and server has no overlap.

> ℹ️ **TIP**: Your integration engine running on the given host might still support a SSL/TLS version that our servers require.

> ℹ️ **NEXT**: Consult documentation of your integration enginge to see what SSL/TLS versions it supports.

> ℹ️ **TIP**: client software might be outdated or missing security updates (can be OS and/or integration engine version).

> ℹ️ **NEXT**: Explore ways to update your client software.