AuthenticationSupport service missing. Cannot authenticate request.

[JoanaAraujo]

Hi All,

We have setup an envirnoment with a TarMk cold standby node for the Authors.

On the stand-by node we cannot login and get the following error:

HTTP ERROR 503 AuthenticationSupport service missing. Cannot authenticate request.

On the primary node we are able to login on both on http and https ports, but on the standby node http port gives the error(and https is disabled).

If we failover to the node and make it the primary, that node will accept http and https logins(and the "new" standby will give the same "AuthenticationSupport service missing" error).

We have checked(on the primary) and all bundles are active and on error.log of the standby the only error is the message(repeated over and over):

11.01.2022 21:54:56.210 *ERROR* [qtp1593332610-68] org.apache.sling.engine.impl.SlingHttpContext handleSecurity: AuthenticationSupport service missing. Cannot authenticate request.
11.01.2022 21:54:56.210 *ERROR* [qtp1593332610-68] org.apache.sling.engine.impl.SlingHttpContext handleSecurity: Possible reason is missing Repository service. Check AuthenticationSupport dependencies.

Can anyone help?

[B_Sravan · Accepted solution]

Hi @JoanaAraujo ,

Seems like your instance is corrupted. If it is your local and if you have backup, it is better to re-install the instance.

if it is higher environment or any other, this issue has been discussed here already, please have a look at this link:
https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/getting-an-authentications... 

[milind_bachani]

Hi @JoanaAraujo 

Please refer to the threads :
https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/authenticationsupport-serv...
https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/getting-an-authentications...

And try the possible fixes because there are multiple reasons for instance to give 503 Authentication missing error, however pretty common reason is abnormal shutdown of server and the suggested fix is to cleanup the indexes(/crx-quickstart/repository/index) and restart.