The current minimum versions are:
- OpenSSL 1.0.2 
- APR 1.4.3

The following version of the libraries are recommended:

- APR 1.7.2 or later, http://apr.apache.org
- OpenSSL 1.1.1t or later, http://www.openssl.org

Older versions should also work but are not as thoroughly tested by the Tomcat
Native team


It is current anticipated that Tomcat Native releases will transition to 1.3.x
at some point in the future when the minimum version will become OpenSSL 1.1.1 and
APR 1.6.3.


The minimum version of OpenSSL is driven by the version of OpenSSL used by
downstream distributions.

The current state of OpenSSL in Debian is:
- OpenSSL 1.1.1n in Debian 10 (EOL end June 2024)
- OpenSSL 1.1.1n in Debian 11 (EOL end June 2026)

And in Ubuntu:
- OpenSSL 1.1.1  in Ubuntu 18.04 LTS (EOL in April 2028)
- OpenSSL 1.1.1f in Ubuntu 20.04 LTS (EOL in April 2030)
- OpenSSL 3.0.2  in Ubuntu 22.04 LTS (EOL in April 2032)

The minimum version of APR is driven by the version of APR used by
downstream distributions.

The current state of APR in Debian is:
- APR 1.6.5 in Debian 10 (EOL end June 2024)
- APR 1.7.0 in Debian 11 (EOL end June 2026)

And in Ubuntu:
- APR 1.6.3 in Ubuntu 18.04 LTS (EOL in April 2028)
- APR 1.6.5 in Ubuntu 20.04 LTS (EOL in April 2030)
- APR 1.7.0 in Ubuntu 22.04 LTS (EOL in April 2032)
