---
title: Troubleshooting
description: The following list indicates some potential problems and resolutions you might encounter with the PingAccess agent for RHEL.
component: pingaccess
version: 9.0
page_id: pingaccess:agents_and_integrations:pa_apache_rhel_troubleshooting
canonical_url: https://docs.pingidentity.com/pingaccess/9.0/agents_and_integrations/pa_apache_rhel_troubleshooting.html
revdate: February 6, 2023
---

# Troubleshooting

The following list indicates some potential problems and resolutions you might encounter with the PingAccess agent for RHEL.

> **Collapse: Agent receives an unknown protocol error when attempting to contact the administrative node**
>
> This can indicate that the operating system is using sha1 for encryption. This protocol is no longer supported by default in PingAccess.
>
> We recommend switching to SHA-256. If you cannot switch to SHA-256, you can re-enable SHA-1:
>
> 1. Open the `run.properties` file.
>
> 2. Add TLSv1 to the protocol list. For example:
>
>    ```
>    tls.default.protocols=TLSv1, TLSv1.1, TLSv1.2, TLSv1.3
>    ```
>
> 3. Add the SHA entries to the cipher suites list. For example:
>
>    ```
>    tls.default.cipherSuites = TLS_CHACHA20_POLY1305_SHA256,\
>                               TLS_AES_256_GCM_SHA384,\
>                               TLS_AES_128_GCM_SHA256,\
>                               TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,\
>                               TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,\
>                               TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,\
>                               TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,\
>                               TLS_DHE_RSA_WITH_AES_128_GCM_SHA256,\
>                               TLS_EMPTY_RENEGOTIATION_INFO_SCSV, \
>                               TLS_RSA_WITH_AES_128_CBC_SHA, \
>                               TLS_DHE_RSA_WITH_AES_128_CBC_SHA, \
>                               TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, \
>                               TLS_ECDH_RSA_WITH_AES_128_CBC_SHA, \
>                               TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
>    ```