Institutions typically use different ways (Shibboleth, LDAP, etc.) to authenticate users. It is difficult to achieve a one-size-fits-all deployment to address all the different authentication is done in OLE. This bottleneck can be cleared by using a reverse proxy.
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If you are experiencing HTTP 501 ("Method Not Implemented") errors, this may be the cause. Check your Apache version and error logs for messages such as "ajp_marshal_into_msgb - No such method PATCH".
Possible Fixes
- Use mod_proxy_http instead of mod_proxy_ajp in your proxy setup.
- Use at least Apache 2.4.4 with mod_proxy_ajp.
- Use mod_jk instead of mod_proxy_ajp.